Operator alterable space for a magazine based library

ABSTRACT

An operator alterable space is described, for use with a data storage library. The library has a frame substantially defines an interior environment and is exposed to an exterior environment. The operator alterable space is adapted to accommodate either a drive module that is capable of storing data to a magazine storage element or a shelf module capable of accommodating at least the magazine storage element whereby the magazine storage element can be disposed in the shelf module. The operator alterable space is accessible from the exterior environment for installing either the shelf module or the drive module via an opening in the frame. The operator alterable space is also accessible to a magazine transport from the interior environment, wherein the magazine transport is capable of moving the magazine storage element to the operator alterable space.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. Ser. No. 10/605,222, filed Sep.16, 2003 which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention is directed to a data cartridge library that isuseful in storing data on a recording medium located in a cartridgeand/or retrieving data from such a recording medium.

BACKGROUND OF THE INVENTION

Presently, data cartridge libraries are primarily used to archive data,i.e., store data that is not immediately needed by the host computer,and provide archived data to the host computer when the data is needed.To elaborate, the typical data cartridge library receives data from ahost computer and causes the data to be stored or recorded on therecording medium located in one or more data cartridges. When the hostcomputer requires some of the data that was previously stored in a datacartridge, a request for the data is sent from the host computer to thelibrary. In response, the library identifies the data cartridge(s) inwhich the desired data is located, retrieves the data from the recordingmedium within the cartridge(s), and transmits the retrieved data to thehost computer system.

Presently, most data cartridge libraries are comprised of: (a) aplurality of storage slots for holding data cartridges with the slotsbeing in fixed locations during operation of the library; (b) one ormore drives that are each capable of writing data onto the recordingmedium located in a data cartridge and/or reading data from therecording medium located in a data cartridge; (c) a cartridge pickerdevice that is capable of moving individual data cartridges between theslots and the drives; and (d) an interface for receiving data from andtransmitting data to a host computer. Such libraries are considered tobe “cartridgebased” data cartridge libraries (hereinafter referred to ascartridge-based libraries) because, during operation of the library, themovement of cartridges to and from the fixed storage slots isaccomplished solely by a cartridge picker device that transportsindividual cartridges. Generally, the operation of a “cartridge-based”library involves using the cartridge picker device: (a) to move acartridge from a fixed storage slot to a drive so that data can beeither written on to or read from the recording medium in a cartridge;and (b) to move a cartridge from a drive to a storage slot.

One approach to implementing storage slots in a “cartridge-based”library is to create a wall with a number of fixed slots. This approachhas a distinct drawback when adding cartridges to the library andremoving cartridges from the library. Namely, the fixed slots requirethe cartridges to be loaded into the slots one at a time and removedfrom the slots one at a time. This drawback is particularly acute insituations in which a library has a large number of slots and a largenumber of cartridges either needed to be inserted into or removed fromthe slots. An example of such as situation is when the library is beinginitially populated with cartridges. In such situations, an operatortypically powers down the library and inserts the cartridges into theslots by hand. Another approach to the implementation of storage slotsin a “cartridge-based” library involves the use of a data cartridgemagazine that an operator can mount or demount from a wall in thelibrary. Typically, the magazine is a box-like structure that has anopen side through which cartridges can be inserted into and removed fromthe magazine, a partitioning structure that defines a number of slotsfor holding data cartridges, and a mounting structure that allows themagazine to be mounted and demounted from a wall in the library. Asignificant advantage of the magazine approach is that an operator, bymanipulating magazines rather than individual cartridges, is able tomore quickly insert a large number of cartridges into a library and morequickly remove a large number of cartridges from a library. However,regardless of whether cartridges are being inserted into or removed fromthe library, the operator is still typically required to power down thelibrary or otherwise disable the cartridge picker device to avoid beinginjured by the device during the mounting or de-mounting of a magazine.

In many instances, only one data cartridge needs to be either insertedinto or extracted from a “cartridge-based” library. In these instances,the powering down of the library or disabling of the cartridge pickerdevice so that an operator can insert or extract the cartridge isundesirable. To address this situation, many “cartridge-based” librariesemploy an entry/exit port that allows an operator to insert a singledata cartridge into the library and extract a single data cartridge fromthe library without being exposed to the cartridge picker device.Because the operator is not exposed to the cartridge picker device, thelibrary does not need to be powered down or the cartridge picker devicedisabled during the insertion or removal operation. Generally, theentry/exit port is comprised of a slot for holding a data cartridge anda device that places the slot in one of two states. In the first state,the slot of the entry port is exposed to the environment exterior to thelibrary such that an operator can access the slot. When the slot is inthe first state, the exit/entry port substantially prevents an operatorfrom accessing the interior of the library by way of the slot and, as aconsequence, prevents the operator from being exposed to injury by thecartridge picker device. In the second state, the slot of the entry/exitport is exposed to the interior of the library such that the cartridgepicker device is able to access the slot. When the slot is in the secondstate, the entry/exit port prevents an operator from accessing theinterior of the library via the slot. For the insertion of a datacartridge into the library, the slot is placed in the first state andthe operator inserts a data cartridge into the slot. The slot is thenplaced in the second state to make the cartridge available to thecartridge picker device for placement elsewhere in the library. For theextraction of a data cartridge, the slot is placed in the second stateand the cartridge picker device places a cartridge in the slot. The slotis then placed in the first state to make the cartridge available to anoperator for removal.

Entry/exit ports that provide the ability to insert multiple datacartridges en masse into a library and extract multiple data cartridgesen masse from a library are also known. Such exit/entry ports aretypically employed in libraries that have a relatively high number ofslots and are used in a manner in which the insertion and/or extractionof several cartridges at a time is desirable but the powering down ordisabling of the cartridge picker device to allow a manualinsertion/extraction of the cartridges is undesirable. For these typesof libraries, the operator is effectively limited to inserting andextracting data cartridges via the entry/exit port. To provide theoperator with the ability to insert or extract several cartridges at atime, the entry/exit port has multiple slots that form a fixed part ofthe port. Alternatively, an entry/exit port is provided that allows amagazine with multiple slots to be inserted into the port by theoperator. With respect to this type of entry/exit port, insertion ofmultiple cartridges into the library is accomplished by placing the portin a first state so that an operator can either: (a) populate a magazinethat is already present in the port with multiple cartridges, or (b)place a magazine and accompanying cartridges into the port. The port isthen placed in a second state so that the cartridge picker device canindividually move each of the cartridges in the magazine to otherlocations within the library. To extract multiple cartridges, the portis placed in the second state and the cartridge picker deviceindividually moves cartridges from various locations in the library tothe magazine. After all of the cartridges that are to be extracted havebeen placed in the magazine, the port is placed in the first state. Oncein the first state, an operator can either individually removecartridges from the magazine or remove the magazine from the port.

In many applications, the user of a cartridge-based library has acurrent need for a library with a particular data cartridge storagecapacity and/or a particular number of drives but anticipates that therewill be a future need for a library with a greater data cartridgecapacity and/or greater number of drives. To address this situation,cartridge-based libraries have been developed that allow the user toinitially acquire a library that satisfies the current needs and whenfuture needs exceed the data cartridge and/or drive capacity of thelibrary, allow the user to expand the library. Certain cartridge-basedlibraries that have this expansion capability expand the library with aunit or units that expand the library horizontally. Othercartridge-based libraries expand the library in a vertical fashion. Ineither case, such cartridge based libraries are in many cases able topass cartridges between the original library and the expansion units byexpanding the cartridge picker system.

In certain cartridge-based libraries, the use of expansion units thatprovide greater data cartridge storage capacity and/or a greater numberof drives and an expandable cartridge picker system is not practicable.For instance, the use of expansion units and an expandable cartridgepicker system is typically not practicable for libraries that employ acartridge picker system that traverses a circular path, which aresometimes referred to as “silo” libraries. Nonetheless, in manysituations, there is a need to transfer cartridges between libraries forwhich the expansion approach is impracticable and to do soautomatically, rather than transfer a cartridge out of one library byits entry/exit port and then have an operator transfer the cartridge tothe entry/exit port of the other library. Consequently, cartridgepass-through ports have been developed that allow one library toautomatically transfer a cartridge to another library, i.e., withoutoperator assistance.

SUMMARY OF THE INVENTION

The present invention is directed to a “magazine-based” data cartridgelibrary that is capable of moving data cartridge magazines within thelibrary, as well as moving individual cartridges within the library. Amagazine-based data cartridge library (hereinafter referred to as amagazine-based library) is comprised of: (a) one or more shelves thatare each capable of holding one or more data cartridge magazines andallowing the one or more data cartridge magazines to be moved to andfrom the shelf system by a robotic device; (b) one or more drives thatare each capable of reading data from and/or writing data to a recordingmedium located in a data cartridge; (c) a magazine transport device formoving a magazine within the library, including the movement of amagazine to and from the shelf system; (d) a cartridge transport formoving data cartridges between a magazine that is moveable within thelibrary and one or more drives that are located in the library; and (e)an interface for receiving data from and transmitting data to a hostcomputer. In contrast, a cartridge-based library does not have theshelves or the magazine transport of a magazine-based library. Further,it should be appreciated that a cartridge-based library does not havethe cartridge transport of a magazine-based library. To elaborate, thecartridge picker in a cartridge-based library moves cartridges to andfrom slots that are at fixed locations during operation of the library.In contrast, the cartridge transport of a magazine-based library movescartridges to and from the slots of a magazine that is capable of beingmoved by the magazine transport device during operation of the library.

A magazine-based library has a number of advantages relative to acartridge-based library. For instance, in one embodiment of amagazine-based library that has multiple drives, cartridges can be“bulk” loaded into the drives. In a bulk load operation, an embodimentof a magazine transport device extracts a magazine from a shelf andmoves the extracted magazine to a location adjacent to the drives, whichare typically situated in a row or column. Once the magazine ispositioned adjacent the drives, an embodiment of a cartridge transportmoves a cartridge into one of the drives and then another cartridge intoanother one of the drives. The cartridge transport continues loadingcartridges in this manner until the desired number of cartridges havebeen loaded. In most cases, the total distance moved by the magazinetransport and the cartridge transport in performing a bulk loading ofthe cartridges will be significantly less than the distance that acartridge picker in a cartridge-based library would move in traversingback and forth between the fixed storage slots and the drives in loadingthe same number of cartridges into individual drives. As a consequence,with other factors being equal, this embodiment of a magazine-basedlibrary is able to load the drives faster than a cartridge-based libraryand in many cases, considerably faster.

One embodiment of the magazine-based library has a layout in which thespace allocated to the magazine transport (i.e., the space within whichthe magazine transport must be able to move within the library toposition magazines at all desired locations within the library) has atleast one dimension that is related to a dimension of the magazineemployed in the library. To elaborate, when a magazine is situated on ashelf in a magazine-based library, the front and rear surfaces of themagazine define a magazine plane with a depth that is equal to thedistance between the front and rear surfaces of the magazine. The spacewithin which the magazine transport operates is also a plane that willbe referred to as a transport plane. The transport plane is parallel tothe magazine plane and, like the magazine plane, has a depth. When themagazine transport removes a magazine from a shelf, the magazinetransport displaces the magazine from the magazine plane into thetransport plane. In one embodiment of the magazine-based library, thedepth of the transport plane is greater than the depth of the magazineplane but less than twice the depth of the magazine plane. Typically,the closer the depth of the transport plane is to the depth of themagazine plane, the more likely the overall volume of space occupied bythe transport plane approaches an optimal volume at which the volume ofthe transport plane is the minimum needed to transport magazines withinthe library. Consequently, a transport plane or space with a depth thatapproaches the depth of the magazine plane can contribute to achieving ahigh data density footprint for the library. The data density footprintis the amount of data that a library is capable of storing when themaximum number of data cartridges that the library is capable ofaccommodating are housed within the library divided by the area of thefloor space or footprint occupied by the library. The depth of thetransport plane is preferably less than about 150% of the depth of themagazine plane and more preferably less than about 130% of the depth ofthe magazine plane. In a further embodiment, the distance between thefront and rear surfaces of the magazine used in the library or the depthof the magazine plane is roughly equal to the depth of the drives usedin the library, i.e., within about +/−20% of the depth of the drives. Byemploying magazines with a length or depth that is related to the lengthor depth of the drive(s) employed in the library, the ability to layoutthe components of the library in a manner that efficiently uses thespace within the library is increased.

Another embodiment of the magazine-based library is particularly able tomove magazines that are relatively heavy when fully populated withcartridges. To elaborate, this embodiment of the library comprises amagazine picker for displacing a magazine towards and away from a shelfand an elevator for moving the magazine picker within the library (anelevator that moves in only one dimension or in multiple dimensions ispossible). To manage fully populated magazines that are relativelyheavy, the magazine picker is comprised of a support surface on whichall or a portion of a magazine can rest and a device that is capable ofmoving a magazine between a shelf and the support. In one embodiment,the support surface comprises a guide structure that serves to orientthe magazine during the transfer of the magazine to or from a shelf andto maintain the orientation of a magazine during movement of the supportwithin the library by the elevator. In another embodiment, the devicefor moving a magazine between the support and a shelf comprises: (a) anengagement device for establishing a connection with a magazine that issufficiently positive to allow the magazine to be moved; and (b) adisplacement device for moving the engagement device so that when theengagement device has engaged a magazine, the magazine can be movedbetween a shelf and the support. In one embodiment, the engagementdevice comprises a member with a surface that is used to “hook” amagazine, an actuator for providing the force to move the member intoand out of engagement with a magazine, and a linkage that constrains themember to rotate about an axis. In operation, the engagement device“hooks” a magazine by using the actuator to rotate the member so thatthe “hooking” surface is in position to engage a magazine. To “unhook”the magazine, the actuator is used to rotate the member so the surfaceis no longer in position to “hook” the magazine.

A further embodiment of the invention provides a method for moving amagazine relative to a shelf in a magazine-based library. The methodinvolves displacing the magazine relative to the shelf in discrete stepsthat each displace the magazine further towards or away from a shelf.For convenience, the method is initially described with respect to themoving of a magazine away from a shelf. The method comprises providing adevice for engaging a magazine and using the device to engage themagazine. Once the magazine has been engaged, the device is displaced tomove the engaged magazine a first distance away from a shelf. After themagazine has been displaced the first distance, the device is disengagedfrom the magazine and moved back towards the shelf. At this point, thedevice re-engages the magazine and is then displaced away from the shelfto move the re-engaged magazine further away from the shelf. In the caseof moving a magazine towards a shelf, the method comprises the steps ofproviding a device for engaging a magazine and using the device toengage the magazine. Once the magazine has been engaged, the device isdisplaced to move the engaged magazine a first distance towards a shelf.After the magazine has been displaced the first distance, the device isdisengaged from the magazine and moved away from the shelf. At thispoint, the device re-engages the magazine and is then displaced towardsthe shelf to move the re-engaged magazine further towards the shelf. Themethod is capable of being implemented with an engagement device that“hooks” a magazine. The method is also capable of being implemented withan engagement device that is an adaptation of the types of devices thatare presently used in cartridge-based libraries to grasp cartridgesbetween two members. Typically, the two members in such devices grasp adata cartridge by either (a) moving one member towards the other member;or (b) moving each member towards the other member. The movement of amember is typically accomplished by either rotating the member about anaxis or linearly translating the member. In any event, such devices areadaptable to grasping magazines and the method is capable of beingpracticed with devices that are so adapted and any other devices thatare capable of engaging a magazine so that the magazine can bedisplaced.

A further embodiment of the invention provides a method for moving amagazine relative to a shelf in a magazine-based library. The method isinitially described with respect to the moving of a magazine away from ashelf. The method comprises the steps of providing a support structurefor holding a data cartridge magazine and providing a device forengaging a magazine. The method further comprises positioning thesupport structure adjacent to the magazine; causing the device to engagethe magazine; and displacing the device and, as a consequence, theengaged magazine away from the shelf such that at least a portion of themagazine is held by the support structure. The method is capable ofbeing implemented with a device that engages a magazine by “hooking” themagazine. The method is also capable of being implemented with varioustypes of devices for engaging a magazine that, in operation, grasp amagazine between two members, rather than “hook” a magazine. The methodis also practicable with any other device that is capable of engaging amagazine so that the magazine can be displaced.

Yet a further embodiment of the invention is directed to a method formoving magazines between different shelves in a magazine-based library.The method comprises the steps of providing a device for engaging amagazine and providing a support structure for holding a magazine. Themethod further comprises positioning the support structure adjacent to amagazine located on a first shelf; causing the device to engage theshelved magazine; and moving the device away from the first shelf to anextent that the engaged magazine is held by the support structure and isno longer held by the first shelf. Further comprising the method is thestep of moving the device towards a second shelf to an extent that themagazine is supported by the second shelf and no longer associated withthe support structure. In one embodiment, the first and second shelvesare situated opposite to one another and separated by a space. In thisembodiment, the support structure is used to bridge the space for thetransfer of the magazine from the first shelf to the second shelf. Themethod is capable of being implemented with a device that “hooks” amagazine. The method is also capable of being implemented with the typesof devices that operate to grasp a magazine between two members, ratherthan “hook” a magazine. The method is also practicable with any otherdevice that is capable of engaging a magazine so that the magazine canbe displaced.

A further embodiment of a magazine-based library comprises a cartridgetransport for moving cartridges to and from a magazine when thecartridges are oriented within the magazine and the library such thatthe faces of the cartridges with the greatest surface area lie in asubstantially vertical plane. At least with respect to certain cartridgeform factors and particular or desired library dimensions, it has beendiscovered that the orientation of cartridges in this manner contributesto a high data density footprint. Data density footprint is the amountof data that a library is capable of storing when the maximum number ofdata cartridges that the library is capable of accommodating are housedwithin the library divided by the floor space occupied by the library. Ahigh data density footprint is important in applications where the floorspace that can be dedicated to data storage is limited and the amount ofdata that needs to be stored is relatively large. One notable example ofsuch an application is a data center that provides off-site “backup” or“mirroring” of the data stored on the computer systems of the datacenter's clients. Such data centers typically want to maximize theamount of data that can be stored over a given floor space. In oneembodiment, the cartridge transport comprises a grasper for grasping adata cartridge and a displacement or actuating device for moving thegrasper such that when the grasper is extracting/inserting a cartridgefrom/into a magazine, the cartridge is linearly displaced such that thecartridge moves within a substantially vertical plane. In oneembodiment, the displacement, in addition to being in vertical plane,has a vertical component. In another embodiment, the displacement has ahorizontal or lateral component. In a further embodiment, an additionalactuating device operates to rotate the grasper about a horizontal axisduring the transport of a grasped cartridge from a magazine to a drive.The rotation, in one embodiment, is about a horizontal axis that allowsa grasped data cartridge to be inserted into a drive with a horizontallyoriented slot for receiving a cartridge. In another embodiment, therotation is about a horizontal axis that allows a grasped data cartridgeto be inserted into a drive with a vertically oriented slot forreceiving a data cartridge. The additional actuating device alsooperates to rotate the grasper about a horizontal axis during thetransport of a grasped cartridge from a drive to a magazine.

Yet another embodiment of a magazine-based library comprises a magazinetransport that is capable of moving a magazine, that when located in thelibrary orients a cartridge such that the face of the cartridge with thegreatest surface area lies in a vertical plane, to a site at which twoor more of the slots of the magazine are accessible by a cartridgetransport. The cartridge transport comprises a grasper for graspingcartridges and a grasper transport that is capable of horizontallydisplacing the grasper such that the grasper can be positioned adjacentto the two slots of a magazine that has been positioned at the notedsite by the magazine transport. In one embodiment, the magazinetransport comprises a support for holding a magazine, a magazineengagement device for moving a magazine between the support and a shelf,and an elevator for moving the support and magazine engagement devicewithin the library. The grasper and the grasper transport areoperatively attached to the elevator and positioned so that the graspertransport is able to move the grasper to a location adjacent to one oftwo or more of the slots of a magazine that is held by the support sothat the grasper can insert/extract a cartridge into/from the magazine.In another embodiment, the grasper and grasper transport are notassociated with the elevator but rather are fixedly positioned adjacentto a drive. In this embodiment, the magazine transport positions amagazine adjacent to the grasper and grasper transport. The graspertransport horizontally moves the grasper to a location adjacent to oneof two or more of the slots of the magazine for insertion or extractionof a cartridge. In a further embodiment, the cartridge transportcomprises an additional actuating device or structure that is used tolinearly displace a cartridge relative to the magazine during extractionof a cartridge from the magazine and insertion of a cartridge into themagazine. In yet a further embodiment, an additional actuating mechanismis employed to rotate the grasper about a horizontal axis to facilitatethe transport of a cartridge between the drive and a magazine.

Another embodiment of a magazine-based library comprises a magazinetransport for moving a magazine within the library, a cartridgetransport for moving a cartridge between a magazine and a drive, and anelevator that is part of both the magazine transport and the cartridgetransport. In one embodiment, the elevator comprises a carriage to whichboth a magazine picker and a grasper are attached, and a surface forholding a magazine. Such a magazine-based library is capable of a “bulkload” operation in which: (a) the magazine picker moves a magazine froma shelf onto the support; (b) the elevator moves the support andassociated magazine to a location adjacent the drives; and (c) thegrasper is then used to repeatedly move a cartridge from the magazineinto one of the drives until the desired number of cartridges have beenloaded. In one embodiment, the cartridge transport comprises a grasperfor grasping the cartridges and a grasper transport for moving thegrasper such that the grasper can be positioned adjacent to at least twoof the slots of a magazine when the magazine is associated with thesupport. In a particular embodiment, the grasper transport is capable ofpositioning the grasper adjacent to each slot of a magazine that isappropriately positioned on the support.

Yet a further embodiment of a magazine-based library comprises a devicefor reading a label that is associated with a magazine, as well aslabels that are associated with any cartridges held by the magazine. In“cartridge-based” libraries there is a need to be able to identifycartridges within the library because a particular cartridge will notnecessarily be permanently associated with a particular storage slot.The cartridge picker in such libraries can move the cartridge from onestorage slot to another storage slot, to an entry/exit port, or toanother library via a pass-through port. Consequently, to be able todetermine which a cartridge is in a particular location within alibrary, the cartridges need to be susceptible to identification.Presently, identification of cartridges is accomplished by associating abar-code label with each cartridge in the library and positioning thebar-code label such that a barcode reader is readily able to read thebar-code associated with the cartridge. However, there is no need in“cartridge-based” libraries that employ magazines to create cartridgestorage slots to be able to identify a magazine within the librarybecause such libraries do not manipulate or move magazines within thelibrary during operation. Consequently, the magazines that are used incartridge-based libraries do not bear labels that identify the magazineand that can be read by any kind of label reader located within thelibrary. However, in a magazine-based library, because the location of amagazine is not fixed and can be changed using a magazine transporter,there is a need to be able to identify each magazine. In one embodiment,the device for reading the magazine label and cartridge labels comprisesa label reader (e.g., a bar code reader) and an actuating device formoving the label reader between a first orientation at which the readeris capable of reading a magazine label and a second orientation at whichthe reader is able to read cartridge labels. In one embodiment, thelabel reader is associated with the element of the cartridge transportthat grasps data cartridges. In another embodiment, the device iscomprised of two label readers, one label reader for reading a magazinelabel and a second reader for reading cartridge labels. In oneembodiment that employs two label readers, the first reader isassociated with the element of the cartridge transport that grasps datacartridges, and the second reader is associated with a magazine pickerthat moves magazines to and from shelves in the library.

Another embodiment of a magazine-based library comprises a cartridgetransport that is capable of accommodating cartridges of differentdimensions. The particular dimensions associated with a data cartridgeare commonly referred to as a form factor. For tape data cartridges,common form factors include DLT (digital linear tape), LTO (linear tapeopen), and SAIT (super advanced intelligent tape). The present inventionprovides a magazine-based library with a cartridge transport that isable to grasp cartridges that conform to two different form factors. Toelaborate, the cartridge transport comprises a housing that serves toconstrain a cartridge in at least one dimension. The housing is capableof adapting to cartridges that have different measurements in onedimension, such as the height dimension. In one embodiment, the housingcomprises a first planar surface and a second planar surface that issubstantially parallel to and separated from the first planar surface.Further, the first planar member is able to move relative to the secondplanar member so that the distance between the two members can beadjusted to accommodate the differences in the distances between twosubstantially parallel surfaces associated with two cartridges that eachconform to a different form factor. In one embodiment, the planarmembers are able to accommodate LTO and DLT tape cartridges, which havedifferent heights (height being the distance between the twosubstantially parallel faces of the cartridge that have the greatestsurface area).

Another embodiment of a magazine-based library comprises an entry/exitport for conveying a magazine between: (a) a space that is interior tothe library and accessible by a magazine transport device that can placea magazine in the port or remove a magazine from the port; and (b) anexterior environment where an operator can place a magazine in the portor remove a magazine from the port. It should be appreciated that suchan entry/exit port is markedly different than the entry/export ports in“cartridge-based” libraries that utilize a magazine to move cartridgesinto and out of a library. In a cartridge-based library that employs anentry/exit port, the cartridge picker cannot move the magazine, thecartridge picker can only move individual cartridges between themagazine associated with the port and other locations in the library. Incontrast, the entry/exit port of a “magazine-based” library allows amagazine picker to move magazines into and out of the port.

In one embodiment, the entry/exit port comprises a tray for supporting amagazine and selectively holding the magazine in a substantially fixedposition relative to the tray during the movement of a magazine betweenthe exterior environment and the space that is interior to the cabinet.The ability to selectively hold the magazine in a fixed position isparticularly important during the transport of a magazine between theexterior environment and the interior space that is accessible by themagazine picker. To elaborate, momentum is imparted to the magazineduring transport of the magazine between the exterior environment andthe interior space. If the magazine was not fixed in place during thetransport, the momentum could possibly carry the magazine into theinterior of the library in a manner that could adversely affect theoperation of the library. In one embodiment, the tray comprises a fixedwall and a spring-loaded, opposing wall that are capable of clamping amagazine in place during transport. When the tray is positioned so thatthe magazine picker can access the tray, the spring-loaded, opposingwall is retracted to unclamp any magazine being supported by the tray sothat the magazine picker can remove the magazine from the tray.

A further embodiment of the entry/exit port comprises a door system thatprevents an operator from accessing the interior of the library via theentry/exit port. In one embodiment, the entry/exit port comprises anexterior door and an interior door that operate such that during thetime that the exterior door is opening to allow an operator to accessthe port, the interior door is closing to prevent the operator fromaccessing the interior of the library via the port and from possiblybeing injured by moving elements within the library. Conversely, duringthe time that the exterior door is closing, the interior door is openingto allow the magazine picker to access the port. In one embodiment, alinkage between the interior and exterior doors is employed to achievethe coordinated operation.

A further embodiment employs a tray for supporting a magazine that movesbetween a position that is exterior to the library so that an operatorcan access the tray and a position that is interior to the library sothat a magazine picker can access the tray. In this embodiment, alinkage is employed that coordinates the opening and closing of thedoors with the movement of the tray. To elaborate, the linkage operatessuch that during the time that the tray is moving from the position thatis exterior to the library to the position that is interior to thelibrary, the exterior door moves from the open position towards theclosed position and the interior door moves from the closed positiontowards the open position. Conversely, during the time that the tray ismoving from the position that is interior to the library to the positionthat is exterior to the library, the exterior door moves from the closedposition towards the open position and the interior door moves from theopen position towards the closed position. In one embodiment, theinterior and exterior doors are substantially planar and are operated ina “draw-bridge” fashion such that each of the doors rotate about an axisthat is substantially parallel to the face of the door. Other doorstructures are feasible, including a door structure that rotates about adifferent axis to move between open and closed positions, a doorstructure that is linearly translated between open and closed positions,and a multi-element door. In a further embodiment, a single actuator isused to achieve the movement of the tray and the interior and exteriordoors. Yet another embodiment of the entry/exit port employs a carouselwith a body that holds a magazine and that rotates about an axis. Thebody serves to prevent an operator from accessing the interior of thelibrary. Consequently, the carousel approach avoids the use of doors.However, the implementation of a carousel entry/exit port is likely toreduce the space available for magazines and/or drives in the library.

Also provided is a magazine that is suitable for use in a magazine-basedlibrary in which magazines are moved within the library. The magazine iscomprised of: (a) a frame that defines a space for accommodating aplurality of data cartridges; (b) a partitioning structure for dividingthe space into a plurality of slots with each slot being capable ofaccommodating a data cartridge and supporting the cartridge such thatwhen the magazine is associated with the magazine-based library, theface of the cartridge with the greatest surface area lies in a verticalplane; and (c) an engagement structure that allows the magazine to beengaged by a magazine picker for movement within the library. In oneembodiment, the engagement structure comprises a hole for use inmagazine-based libraries that employ a magazine picker that utilizes amember to “hook” magazines. Another embodiment employs an engagementstructure that is adapted for use with a magazine picker that utilizestwo members to grasp a magazine. In one embodiment, the engagementstructure comprises a pair of holes. In another embodiment, theengagement structure comprises a pair of protrusions that extend beyonda surface or surfaces of the frame. Yet a further embodiment comprises apair of indentations in a surface or surfaces of the frame. Yet afurther embodiment of the magazine comprises a flag structure for use indetermining when a magazine picker has engaged the magazine. In oneembodiment, the flag structure comprises an element that blocks anoptical signal when the magazine picker has engaged the magazine.

Another embodiment of the magazine comprises a “label” structure for usein identifying the magazine within the library so that, for example, thelocation of the magazine in the library can be tracked. There is no needin a “cartridge-based” library that employs magazines to create fixedstorage slots to identify the magazines during the operation of thelibrary because the library does not manipulate or move magazines withinthe library during operation. As previously noted, magazines incartridge-based libraries primarily serve to make it easier for anoperator to hand load/unload a large number of cartridges into/from thelibrary. In contrast, in a magazine-based library, magazines aremanipulated during operation of the library and, as a consequence, thereis a need to be able to identify a magazine within a library. In oneembodiment, the label structure comprises an indentation in a surface ofthe magazine that is capable of accommodating an adhesive label, such asan adhesive bar-code label. Another embodiment comprises a receptaclethat is associated with the magazine and that is capable of receiving alabel or other identifier, such as a radio frequency identification RFIDtag. In yet another embodiment, an identifier, such as an RFID tag, isembedded within the magazine. Identifiers with fixed or programmableidentification information are also feasible.

Another embodiment of the magazine comprises a structure for inhibiting,when the magazine is on a shelf within a magazine-based library,movement of the magazine other than movement attributable to themagazine picker. In one embodiment, the structure comprises a detentthat cooperates with a notch associated with a shelf to hold themagazine in a desired location on a shelf. The engagement between thenotch and the detent serves to resist forces that might displace themagazine. The resistance provided by this engagement is not, however,great enough so that it cannot be overcome by a magazine picker. Afurther embodiment of the structure comprises one portion of an activelatching mechanism, the other portion of the latching mechanism beingassociated with the shelf. In one active latch embodiment, the structureassociated with the magazine comprises a receptacle that is designed toengage an active element associated with the shelf. In another activelatch embodiment, the structure associated with the magazine comprisesan active element that is adapted to engage a receptacle associated witha shelf. One such active element comprises a cantilevered detent. Inoperation, the cantilever provides a spring force that must be overcometo disengage the detent from the receptacle and, as a consequence,resists forces that might displace the magazine from a preferredlocation.

A further embodiment of a magazine-based library comprises a drive bayfor holding a drive in an operative position within the library andfacilitating relatively speedy insertions and extractions of the drive.Most drives have a front face with a slot for receiving a data cartridgeand rear face with one or more plugs for receiving power, controlsignals, and data signals. In many cartridge-based libraries, when sucha drive is operatively situated in a library, the front face of thedrive is accessible to the cartridge picker. The drive is also typicallysituated near a removable panel or door of the library housing so thatan operator can readily access the drive. Further, the drive istypically attached to a frame to prevent the drive from moving duringoperation of the library. To remove or replace such a drive, theoperator has to remove the panel or open the door to obtain access tothe drive, disconnect the drive from all of the electrical connectorsthat are providing power, control signals, and data signals to thedrive, and then unfasten the drive from the frame. In many situations,the library is powered down during such an operation. The magazine-basedlibrary with a drive bay substantially reduces the work and, hence, thetime required for such operations. To elaborate, in one embodiment, thedrive bay comprises a housing with two open sides, where one of the opensides is exposed to the cartridge transport and the other open side isexposed to an environment that is accessible to an operator so that theoperator can insert or extract a drive from the housing. Furthercomprising the drive bay is a sled that is capable of holding a drive.The sled comprises an electrical connector with one or more drive plugsthat mate with the plug(s) on the rear face of the drive, one or moresled plugs, and one or more electrical conductors extending between thedrive plug(s) and the sled plug(s). The sled plug(s) is/are oriented soas to face towards the first open side of the housing, i.e., towards thecartridge transport. The drive bay further comprises housing plug(s)that face the second opening or the area accessible to the operator. Thehousing plug(s) is/are positioned in the housing so that when anoperator inserts the sled into the housing with the proper orientation(i.e., such that if the sled held a drive, the front face of the drivewould be accessible to the cartridge transport), the sled plug(s) engagethe housing plug(s). As a consequence, the insertion of a drive into thelibrary is accomplished by pushing a sled with the drive into thehousing such that the sled plug(s) and the housing plug(s) engage oneanother. Conversely, removal of a drive from the library is accomplishedby extracting the sled and drive form the housing, which causes the sledplug(s) and housing plug(s) to disengage from one another. Consequently,the drive bay eliminates the need for an operator to spend timedisconnecting/connecting cables from plug(s) associated with the rearface of the drive during the extraction/insertion of a drive. Further,since the drive is attached to the sled and not a fixed frame within thelibrary, the drive bay eliminates the need to spend timedetaching/attaching a drive from/to such a frame. In one embodiment, thedrive bay housing is comprised of multiple sub-bays with each sub-baycapable of accommodating a sled and having a housing plug forestablishing an electrical connection with a sled residing in thesub-bay.

In yet another embodiment, a magazine-based library comprises anoperator alterable space within the housing, i.e., a space whosefunction in the library is subject to a choice by an operator. Thealterable space is capable of accommodating at least two different typesof library modules. Among the possible types of modules are shelvingmodules and drive modules. The alterable space is defined by a firstopen side that is accessible to the cartridge transport and/or magazinepicker and a second side that is accessible to an operator. Associatedwith the alterable space is a mounting structure that allows a module tobe readily mounted within the library or demounted from the library.Among the possible modules is a drive bay module that, in addition tothe features of a drive bay described above, also has a drive baymounting structure that cooperates with the library mounting structureto facilitate securing the module within the library and removing themodule from the library. Another module is a magazine bay module thatprovides one or more shelves, each for holding at least one magazine.The magazine bay module has a magazine bay mounting structure thatcooperates with the library mounting structure to facilitate securingthe magazine bay within the library and removing the module from thelibrary.

A further embodiment of a magazine-based library comprises a powersystem that is used to provide power to the drive(s) within the libraryand that allows the space within the library to be utilized moreefficiently. In many cases, the power system allows more data cartridgesto be housed within a library relative to a library that employs atypical power system. This advantage is particularly discernable inlibraries that employ multiple drives. To elaborate, most data cartridgelibraries include one or more power supplies for providing power to thedrive or drives within the library. In libraries that employ multipledrives, power is typically conveyed from the power supply or suppliesvia multiple cables, each with a circular cross-section and each with aconductor surrounded by an insulating cover. Typically, these cables arebundled together. This bundle of cables typically has a cross-sectionthat is roughly circular. The cross-sectional shape of the bundle makesit awkward to “fit” the bundle with other elements of the library toefficiently utilize the space within the library. The embodiment of themagazine-based library comprises a power supply and a conductorstructure for distributing power produced by the power supply to thedrive(s) in the library that is flat, i.e., has two external and flatsurfaces that are separated from one another and substantially parallelto one another. For the distribution of power to a given number ofdrives, the distance between the flat external surfaces is less than thediameter of a bundle of circular conductors. This reduced dimensiontypically allows the space within the library to be more efficientlyused and, in many cases, allows a greater number of data cartridges tobe stored within the library. Further, the flat shape of the conductorlends itself to being integrated with the other components of thelibrary, many of which are box-shaped, so that the space within thelibrary can be more efficiently used relative to libraries that employpower conductors with circular cross-sections and bundles of suchconductors.

Further, the insulating covers associated with the conductors in abundle of cables may provide more insulation than is needed toelectrically insulate the conductors from one another. Consequently, theinsulating covers occupy more space over a diameter of the cross-sectionof the bundle than is needed. In one embodiment, the conductor iscomprised of a plurality of laminated electrical conductors that areseparated from one another by insulating material. In a transit betweenthe two external flat surfaces, the amount of space dedicated toinsulating material is less than that for a comparable bundle of cables.Consequently, relative to a bundle of cables, the conductor structureprovides additional space for other uses.

Yet another embodiment of the invention is directed to a method thatallows a user to upwardly scale or expand the size of a magazine-basedlibrary in a modular manner. The method comprises the step of providinga magazine-based library with a cabinet surface that is alterable toform a passageway through the cabinet so that the library can be joinedto an add-on module and magazines can be transferred between the libraryand the add-on module. The magazine-based library further comprises anelevator structure that is used to horizontally displace a magazinepicker that is capable of moving magazines to and from the shelves inthe library. The method further comprises the step of providing anadd-on module with a side surface that is either alterable to form apassageway or already has a passageway. The add-on cabinet can take anumber of forms. For example, the add-on module may be able toaccommodate a shelf, multiple shelves, a drive, multiple drives,combinations of the foregoing elements, or be a self-sufficientmagazine-based library. In one embodiment, the method further comprisesreplacing whatever portion(s) of the elevator structure in the libraryserves to limit the horizontal range over which the magazine picker canbe moved within the library with a longer structure that extends throughthe passageways of the library and the add-on. In another embodiment,the method comprises the further step of providing an add-on to theexisting elevator structure such that an elevator is modularly expandedand the resulting expanded elevator is capable of transporting themagazine picker through the passageways of the library and the add-on.In yet a further embodiment, the add-on has its own magazine transportdevice and the two magazine transport devices (one associated with thelibrary and the other associated with the add-on) are capable ofdirectly passing a magazine from one to the other. In yet anotherembodiment, the add-on comprises a separate magazine transport devicefrom that of the library. However, the two magazine transports areincapable of directly passing a magazine from one to another.Consequently, the method comprises the further step of providing a thirdmagazine transport device that serves as an intermediary transportdevice between the transport device associated with the library and thetransport device associated with the add-on.

The present invention is also directed to a magazine-based library thatis capable of moving magazine data storage elements, as well as datacartridge magazines. A magazine data storage element comprises aplurality of disk drives, a frame that supports the plurality of harddisk drives, electrical and/or optical connection circuitry thatestablishes signal and power paths between the hard disk drives and amagazine-drive connector, and a transport structure for engagement by amagazine transport device associated with the library.

To transfer data between a magazine data storage element and anothercomputer device, a magazine data storage element drive is employed. Themagazine data storage element drive comprises a frame for supporting amagazine data storage element and electrical and/or optical connectioncircuitry for use in establishing an electrical and/or opticalconnection between a magazine data storage element and another computerdevice. The electrical and/or optical connection circuitry is comprisedof a drive-magazine connector that is adapted to engage themagazine-drive connector of a magazine data storage element, adrive-device connector for establishing electrical and/or opticalconnections with another computer device, and conductors extendingbetween the drive-magazine connector and the drive-device connector.

The magazine-based library that is capable of moving magazine datastorage elements and data cartridge magazines is comprised of: (a) oneor more shelves that are each capable of holding one or more magazines,where a magazine can be either a magazine data storage element or datacartridge magazine, and allowing the one or more magazines to be movedto and from the shelf system by a robotic device; (b) at least onemagazine data storage element drive that is capable of reading data fromand/or writing data to a magazine data storage element; (c) at least onedata cartridge drive that is capable of reading data from and/or writingdata to a recording medium located in a data cartridge; (d) a magazinetransport device for moving a magazine within the library, including themovement of a magazine data storage element between a shelf and amagazine data storage element drive; (e) a cartridge transport formoving data cartridges between a data cartridge magazine that ismoveable within the library and the data cartridge drive; and (f) aninterface for receiving data from and transmitting data to a hostcomputer.

In one embodiment, the magazine-based library is adapted to operate onmagazine data storage elements and data cartridge magazines that havecommon or standardized transport and dimensional features thatfacilitate the movement and storage of the magazines within the library.This standardization reduces the complexity of the library. For example,by having common transport features, the same elements of the magazinetransport device that are used to engage a magazine data storage elementare also used to engage a data cartridge magazine, thereby avoiding theneed for a magazine transport device with one structure for engaging amagazine data storage element and another structure for engaging a datacartridge magazine.

The present invention is also directed to a magazine-based library thatis capable of moving magazine data storage elements. The magazine-basedlibrary is comprised of: (a) one or more shelves that are each capableof holding one or more magazine data storage elements, and allowing theone or more magazine data storage elements to be moved to and from theshelf system by a robotic device; (b) at least one magazine data storageelement drive that is capable of reading data from and/or writing datato a magazine data storage element; (c) a magazine transport device formoving a magazine data storage element within the library, including themovement of a magazine data storage element between a shelf and amagazine data storage element drive; and (d) an interface for receivingdata from and transmitting data to a host computer.

The present invention is further directed to a magazine data storageelement comprised of a plurality of disk drives, a frame that supportsthe plurality of hard disk drives, electrical and/or optical connectioncircuitry that establishes signal and power paths between the hard diskdrives and a magazine-drive connector, and a transport structure forengagement by a magazine transport device associated with amagazine-based library. In one embodiment, each of the hard disk drivescomprises a serial signal interface (e.g., a serial ATA interface). Inyet a further embodiment, the hard disk drives each have the sameexternal dimensions. Another embodiment employs disk drives that eachhave the same disk size (e.g., 2½″). Yet another embodiment employs anelectrical and/or optical connection circuitry that comprisesmultiplexing circuitry that allows the path or “pin” count of themagazine-drive connector to be less than the cumulative path or “pin”count associated with the interfaces of the hard disk drives.

The present invention also provides a drive for a magazine data storageelement that is comprised of: (a) a frame for supporting a magazine datastorage element; and (b) an electrical and/or optical interconnectstructure for transmitting power to a magazine data storage element andconveying signals to and from the magazine data storage element. Theelectrical and/or optical interconnect structure is comprised of adrive-magazine connector for establishing electrical and/or opticalconnections with the magazine-drive connector of a magazine data storageelement, a drive-device connector for establishing electrical and/oroptical connections with another device (such as a library or a hostcomputer), and suitable electrical and/or optical conductors extendingbetween the drive-magazine connector and the drive-device connector.

In one embodiment of the drive, the drive-magazine connector iscomprised of a plurality of spring-loaded pins, with each pin located soto contact a conductive pad associated with the magazine-driveconnector. The use of spring-loaded pins reduces occurrences of pinbreakage that could render the drive inoperative relative to a driveplug that employs static pins. Reducing the occurrences of pin breakageis considered important in applications in which the drive is likely toexperience frequent loading and unloading of magazine data storageelements, such as in a magazine-based library.

Another embodiment of the drive comprises a six-sided box-like housingthat conforms to certain standardized dimensions of another type ofdrive. In one embodiment, the housing conforms to the standardizeddimensions of an LTO tape drive, which has a height of approximately 3¼″to 3⅜″ and a width of approximately 5¾″ to 5⅘″. Conformance tostandardized dimensions of other drives is also feasible. By employing ahousing that conforms to the standardized dimensions of another type ofdrive, the drive is more likely to be incorporated into the design ofvarious computer devices, such as data storage libraries, or replaceother types of the drives in such devices. It should, however, beappreciated that the drive is also capable of stand-alone operation,i.e., the drive does not needed to be incorporated into another computerdevice but can be directly connected to a host computer.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a block diagram of a magazine-based data cartridge librarythat illustrates necessary and optional features of the library;

FIGS. 2A-2E are plan views of five rectilinear layouts for amagazine-based data cartridge library;

FIGS. 3A-3G are plan views of seven cylindrical layouts for amagazine-based data cartridge library;

FIGS. 4A and 4B are plan view of two moving shelf layouts for amagazine-based library;

FIGS. 5A-5C are a perspective view of a drive, a front view of the drivein a vertical orientation, and a front view of the drive in a horizontalorientation;

FIGS. 6A-6C are perspective views of the exterior of an embodiment of amagazine-based data cartridge library (hereinafter library);

FIG. 7A is a perspective view of the embodiment of the library shown inFIGS. 6A-6C with the various elements, such as certain cabinet surfacesremoved, and the library populated with magazines;

FIG. 7B is a perspective view of the embodiment of the library shown inFIGS. 6A-6C with certain elements removed, including all but one drivebay, and populated with a few magazines;

FIG. 8A is a perspective sectional interior view of the library withcertain features removed, such as the entry/exit port, and the shelvesin the view fully populated with magazines;

FIG. 8B is a perspective-sectional interior view of the library that isfully populated with drives and the shelves in the fully populated withmagazines;

FIGS. 9A-9B illustrate an LTO tape cartridge;

FIGS. 10A-10B illustrate a SAIT tape cartridge;

FIGS. 11A-11B illustrate a DLT tape cartridge;

FIGS. 12A-12D illustrate an embodiment of a magazine that is capable ofaccommodating both LTO and SAIT tape cartridges;

FIGS. 13A-13B are cross-sectional views of the magazine shown in FIGS.12A-12D that respectively show an LTO tape cartridge and a SAIT tapecartridge within the magazine;

FIGS. 14A-14B illustrate an embodiment of a magazine that is capable ofaccommodating a DLT tape cartridge;

FIG. 15 is a cross-sectional view of the magazine shown in FIGS. 14A-14Bthat shows a DLT tape cartridge within the magazine;

FIG. 16 is a schematic plan view of the general layout of the library;

FIGS. 17A-17B respectively are a front perspective view of an embodimentof a dual entry/exit port and a rear view of the dual entry/exit port;

FIGS. 18A-18F illustrate various elements of one port of the dualentry/exit port;

FIGS. 19A-19E illustrate the operation of the port shown in FIGS.18A-18E in moving a magazine from an exterior environment to a space inwhich the magazine is accessible by a magazine transport device;

FIGS. 20A-20E illustrate examples of alternative door structures for anentry/exit port;

FIGS. 21A-21B illustrate a carousel entry/exit port;

FIGS. 22A-22C respectively illustrate an embodiment of a shelf capableof holding five magazines, an embodiment of a cleat that is associatedwith the shelf, and the relationship between the shelf and magazine;

FIGS. 23A-23C are respectively a front perspective view of an embodimentof a four unit, drive bay assembly populated with four drives, a rearperspective of the drive bay assembly, and a rear view of an embodimentof a ladder frame that is used to hold the drive bay assembly in thelibrary;

FIGS. 24A-24F illustrate features of the housing portion of the drivebay assembly;

FIG. 25 illustrates the plug interface of a typical drive;

FIGS. 26A-26C illustrate the sled portion of the drive bay assembly;

FIGS. 27A-27E illustrate an embodiment of a power supply system thatutilizes a flat power conductor to provide DC power to the drives in thelibrary;

FIGS. 28A-28B illustrate an embodiment of a magazine bay assembly;

FIGS. 29A-29H illustrate features of an embodiment of an elevator thatis used to move a magazine picker;

FIGS. 30A-30G illustrate an embodiment of a magazine picker;

FIGS. 31A-31L are cross-sectional and free body diagrams that illustratethe operation of the magazine picker in moving a magazine from one shelfto another shelf;

FIG. 32 illustrates an alternative magazine engagement device;

FIGS. 33A-33N illustrate an embodiment of a cartridge transport;

FIGS. 34A and 34B respectively illustrate the range of motion of thehousing of the cartridge transport and the ability of a bar code readerto read a bar code label that identifies a magazine and a bar code labelthat identifies a cartridge;

FIGS. 35A-35C illustrate steps associated with moving a data cartridgebetween a magazine and a drive;

FIGS. 36A-36G are free body diagrams that illustrate an embodiment of acartridge transport unit extracting/inserting a data cartridge from/intoa magazine;

FIGS. 37A-37G are free body diagrams that illustrate an embodiment of acartridge transport unit inserting/extracting a data cartridge into/froma drive;

FIG. 38 illustrates the relationship between the space occupied bymagazines resident in the library and the space utilized by the magazinetransport and cartridge transport in the library;

FIG. 39 illustrates the controller and the relationship of thecontroller to the electrical elements in the library and the powerdistribution system;

FIGS. 40A-40F illustrate alternative embodiments of magazines thatoperatively orients cartridges within a magazine-based data cartridgelibrary such that the face of the cartridge with the greatest surfacearea lies in a vertical plane;

FIGS. 41A-41B illustrate an alternative embodiment of a magazine thatoperatively orients cartridges within a magazine-based data cartridgelibrary such that the face of the cartridge with the greatest surfacearea lies in a vertical plane;

FIG. 42 illustrates an alternative embodiment of a magazine that isoperative with the library;

FIGS. 43A and 43B respectively illustrate an expanded library and aschematic representation of the process for producing the expandedlibrary;

FIGS. 44A-44B schematically illustrate alternative methods of producingan expanded library;

FIGS. 45A-45E illustrate various embodiments of magazine pass-throughports for passing magazines between magazine-based libraries;

FIGS. 46A-46C are perspective views of an embodiment of a magazine datastorage element;

FIG. 47 is an exploded view of the magazine data storage elementillustrated in FIGS. 46A-46C;

FIGS. 48A-48B are perspective views of a serial ATA 2½″ drive that isused in the magazine data storage element shown in FIGS. 46A-46C;

FIG. 49 illustrates the interior of the tray of the magazine datastorage element shown in FIGS. 46A-46C;

FIG. 50 is a perspective view of a cage that is used to hold threeserial ATA drives in the magazine data storage element shown in FIGS.46A-46C;

FIGS. 51A-51B are perspective views of the electrical connectionstructure of the magazine data storage element shown in FIGS. 46A-46C;

FIG. 51C is an embodiment of an electrical connection structure thatcomprises a serial multiplexer;

FIG. 51D is an embodiment of an electrical connection structure thatcomprises a serial/parallel converter;

FIGS. 52A-52B are exterior perspective views of a drive for theembodiment of a magazine data storage element shown in FIGS. 46A-46C;

FIGS. 53A-53D are perspective views of interior features of the driveshown in FIGS. 52A-52B;

FIGS. 54A-54B illustrate the disengaged and engaged state of the driveshown in FIGS. 52A-52B;

FIGS. 55A-55D illustrate the operation of the embodiment of a magazinepicker shown in FIGS. 30A-30G in loading the embodiment of a magazinedata storage element shown in FIGS. 46A-46C into the embodiment of adrive shown in FIGS. 52A-52B.

DETAILED DESCRIPTION

The present invention is directed to a magazine-based data cartridgelibrary that is capable of moving data cartridge magazines within thelibrary, as well as moving individual cartridges within the library.

With reference to FIG. 1, the present invention is directed to amagazine-based data cartridge library 100 comprised of: (a) a frame 102for supporting the other elements of the library; (b) a shelving system104 for supporting at least two data cartridge magazines 101 wherein adata cartridge magazine 101 is adapted to hold a plurality of datacartridges (not shown); (c) one or more drives 106 that are each capableof writing and/or reading data to/from a recording medium in a datacartridge; (d) a magazine transport 108 for moving a magazine 101 withinthe library 100; (e) a cartridge transport 110 for moving a datacartridge between a magazine 101 and a drive 106; and (f) an interface112 for communicating with a host computer (not shown) that uses thelibrary 101 to store data.

As noted, the frame 102 provides a support for the other elements of thelibrary 100. In addition, the frame 102 may comprise one or moreexterior surfaces that form a cabinet for enclosing most of thecomponents of the library 100. [The frame may further define an interiorspace 102]. Typically, the cabinet establishes an environment whosetemperature can be controlled for the benefit of the elements of thelibrary 100 housed within the cabinet. The cabinet also commonly servesas a barrier to contaminants that could adversely affect the operationof the elements housed within the library 100. Additionally, the cabinetis also useful in preventing an operator from accessing the space withinthe cabinet during operation of the library 100 and potentially beinginjured by the moving elements within the library 100.

There are a number of devices that do not necessarily need to be part ofthe magazine-based-data cartridge library 100 (i.e., not supported bythe frame 102) but are nonetheless needed for the library 100 tofunction and, as a consequence, typically are part of the library 100.Among these devices are a power supply system 114 (which may becomprised of multiple power supplies) and a controller 116 for managingthe operations of the library 100. Environmental devices 118, such asfans, fins, heat pipes, etc., are additionally incorporated into thelibrary 100 to manage excess heat build-up beyond what the library 100is able to passively dissipate.

Some embodiments of the present invention can include additionalfeatures for enhancing library 100 functionality, such as an entry/exitport 120, a pass-through port 122 and an operator interface 124, to namethree examples. An entry/exit port 120 can facilitate movement of amagazine in and out of the library 100, a pass-through port 122 canfacilitate movement of a magazine between two libraries (such as whenadjacent and working together to share at least one magazine), and anoperator interface 124 can facilitate operator command interaction withthe library 100.

There are several possible layouts for the magazine-based cartridgelibrary 100, consistent with embodiments of the present invention. Manyof these layouts can be characterized or typed as rectilinear orcircular/cylindrical. In a rectilinear type, magazine-based datacartridge library 100, at least the drive or drives 106 and the shelf orshelves of the shelf system 104 are laid out along: (a) a straight lineor plane; or (b) along multiple straight lines or planes that areparallel and/or perpendicular to one another as will be furtherelaborated in the disclosure of FIGS. 2A-2E. More specifically, in arectilinear type library, the face of a drive 106, comprising areceptacle for receiving a data cartridge (not shown), is oriented suchthat the direction that the data cartridge is displaced when thecartridge is either inserted or extracted from the receptacle by thecartridge transport 110 is substantially perpendicular to a straightline or plane. Similarly, a shelf of the shelf system 104 in therectilinear type library is oriented such that the direction that amagazine 101 is displaced when the magazine 101 is either associatedwith a shelf of the shelf system 104 or removed from a shelf of theshelf system 104 by the magazine transport 108, is substantiallyperpendicular to a straight line or plane. Typically, most of the otherelements of the library 100 are also laid out in the same manner.

FIGS. 2A-2E are plan views of five different rectilinear type layoutsfor the magazine-based data cartridge library 100. In the layoutillustrated in FIG. 2A, a drive 128 (or drives) and/or a shelf 130 (orshelves) are oriented along a straight line/plane 132. A robot 134 isprovided that cumulatively represents the magazine transport 108 and thecartridge transport 110. In this embodiment, the robot 134 is capable ofaccessing the drive(s) 128 for purposes of inserting or extracting datacartridges (not shown) as indicated by the two-way arrow 129. The robot134 is further capable of accessing the shelf/shelves 130 to displace amagazine 101, such as to remove for example, as indicated by the two-wayarrow 131. With respect to the rectilinear type layouts shown in FIGS.2B-2E, the drive 128 and shelf 130 elements retain the same referencenumbers as those elements bear in FIG. 2A. Additionally, the two-wayarrows, such as arrow 131, indicate an access locations to drive 128 andshelf 130 elements. In the embodiment illustrated in FIG. 2B, at leastone drive 128 and/or at least one shelf 130 is/are laid out alongline/plane 136A, and at least one drive 128 and/or at least one shelf130 is/are laid out along line/plane 136B, which is parallel toline/plane 136A. In the embodiment illustrated in FIG. 2C, at least onedrive 128 and/or at least one shelf 130 is/are laid out along line/plane138A, and at least one drive 128 and/or at least one shelf 130 is/arelaid out along line/plane 138B, which is perpendicular to line/plane138A. With respect to the embodiment of FIG. 2D, at least one drive 128and/or at least one shelf 130 is/are laid out along each of lines/planes140A, 140B and 140C, with lines/planes 140A and 140B being parallel toeach other and perpendicular to line/plane 140C. In the embodimentillustrated in FIG. 2E, at least one drive 128 and/or at least one shelf130 is/are laid out along each of lines/planes 142A-142D, withlines/planes 142A, 142B being parallel to one-another, and withlines/planes 142C, 142D being parallel to one another and perpendicularto the parallel lines/planes 142A, 142B. It should be appreciated thateach of the embodiments comprises at least one drive 128. Further, eachembodiment comprises at least one shelf 130 that is capable ofsupporting two or more magazines 101, from FIG. 1, or multiple shelves130 that cumulatively support two or more magazines 101. It should alsobe appreciated that the illustrated location of a drive 128 or shelf 130along a line/plane is merely illustrative and that the actual locationof a drive 128 or shelf 130 can be anywhere along a line/plane. Itshould also be appreciated that, while the robot 134 cumulativelyrepresents the magazine transport 108 and cartridge transport 110, themagazine transport 108 and the cartridge transport 110 may share one ormore elements or be entirely separate from one another. It should befurther appreciated that there may be other rectilinear layouts for themagazine-based data cartridge library capable of cooperating with amagazine transport 108.

Referring back to the elements of FIG. 1, in a circular/cylindricaltype, magazine-based data cartridge library 100, the drive or drives 106and shelf or shelves of the shelf system 104 are laid out along radiallines that have a common center and/or along one circular arc ormultiple, concentric circular arcs. More specifically, in a circulartype library, the face of a drive 106 comprises a receptacle forreceiving a data cartridge (not shown) is oriented such that thedirection that the data cartridge is displaced when the cartridge iseither inserted or extracted from the receptacle is either: (a)substantially along a radial line/plane, (b) substantially along aline/plane that is parallel to a radial line/plane, or (c) along a linethat is tangent to a circular arc as will be further elaborated in thedisclosure of FIGS. 3A-3G. Similarly, a shelf of the shelf system 104 ina circular type library is oriented such that the direction that amagazine 101 is displaced when the magazine 101 is either associatedwith a shelf or removed from a shelf of the shelf system 104 by themagazine transport 108 is either: (a) substantially along a radialline/plane, (b) substantially along a line/plane that is parallel to aradial line/plane, or (b) along a line that is tangent to a circulararc.

FIGS. 3A-3G are plan views of seven different circular/cylindrical typelayouts for the magazine-based data cartridge library 100. In the layoutillustrated in FIG. 3A, a drive 146 (or drives) and/or shelf 148 (orshelves) are respectively oriented along radial lines 150A, 150B thathave a common center 152 and along a circular/cylindrical arc 153. Arobot 154 is provided that cumulatively represents the magazinetransport 108 and the cartridge transport 110 of FIG. 1. The robot 154is capable of accessing the shelf 148 disposed along thecircular/cylindrical arc 153 for transferring one or more data cartridgemagazines 101 to and from the shelf 140 as indicated by the two-wayarrow 147B. The robot 154 is also capable of accessing the drive 146also disposed along the circular/cylindrical arc 153 for transferringone or more data cartridges (not shown) to and from the drive 146 asindicated by the two-way arrow 147A. As illustrated in this embodiment,the robot 154 is adapted to accessing the drive 146 and shelf 148 bymoving along an arc following the circular/cylindrical arc 153 for asshown by the two-way arrow 145. With respect to the circular/cylindricaltype layouts shown in FIGS. 3B-3G, the term drive 146 refers to one ormultiple drives and the term shelf 148 refers to one or more shelves.Additionally, reference numbers for elements common to the variousembodiments have been retained as a matter of convenience. In theembodiment illustrated in FIG. 3B, at least one drive 146 and/or atleast one shelf 148 is/are laid out along a radial line(s) 150A and 150Brespectively and along a first circular/cylindrical arc 156A, and atleast one drive and/or at least one shelf collectively shown by adrive(s) and/or shelf block 147 is/are laid out along a radial line(s),herein radial line 150A, and along a second circular/cylindrical arc156B that is concentric to the circular arc 156A. The robot 154 moves ina space that is located between the two concentric arcs 156A, 156B. Itshould be appreciated that the embodiments illustrated in FIGS. 3A and3B are each capable of being implemented such that the shelf or shelves148 and drive or drives 146 are laid out along a circular/cylindricalarc 156A that defines a complete or substantially complete circle orcylinder. In the embodiment illustrated in FIG. 3C, at least one drive146 and/or at least one shelf 148 is/are laid out along radial lines150A and 150B respectively and along a circular/cylindrical arc 156A,and at least one drive and/or shelf 147 is/are laid out along a tangentline 158 to a circular/cylindrical arc 160 that typically represents thepath traveled by an element of the robot 154. The robot 154 is capableof accessing the drive(s) and/or shelf 147 as indicated by the two-wayarrow 147D. The embodiment illustrated in FIG. 3D is a combination ofthe characteristics or features noted with respect to the embodimentsshown in FIGS. 3B and 3C. In the embodiment illustrated in FIG. 3E, atleast one drive and/or shelf 147 is/are laid out along a tangent line162A to the circular/cylindrical arc 160, and at least one drive and/orshelf 147 is laid out along a tangent line 162B to thecircular/cylindrical arc 160. The embodiment illustrated in FIG. 3F is acombination of the characteristics or features noted with respect to theembodiment shown in FIGS. 3B and 3E. In the embodiment illustrated inFIG. 3G, at least one drive and/or shelf 147 is/are laid out along thetangent line 158 of the circular/cylindrical arc 160. In yet a furtherembodiment (not shown), at least one drive and/or shelf 147 are locatedalong each of two or more circular arcs, such as the two concentric arcs156A, 156B, with a common center 152 wherein an element of the robot 154is cable of moving between the arcs. It should be appreciated that eachof the embodiments comprises at least one drive 146. Further, eachembodiment comprises at least one shelf 148 capable of supporting two ormore magazines 101 or multiple shelves 148 that cumulatively support twoor more magazines 101. It should also be appreciated that theillustrated location of a drive 146 or shelf 148 along acircular/cylindrical arc, such as arc 156A, is merely illustrative andthat the actual location of a drive 146 or shelf 148 can be anywherealong the circular/cylindrical arc. It should also be appreciated that,while the robot 154 cumulatively represents the magazine transport 108and cartridge transport 110, the magazine transport 108 and thecartridge transport 110 may share one or more elements or be entirelyseparate from one another. It should be further appreciated that theremay be other circular layouts for the magazine-based data cartridgelibrary 100 with features capable of cooperating with a magazinetransport 108.

Yet another possible layout for the magazine-based data cartridgelibrary 100 of FIG. 1 is a movable-shelf type in which at least twoshelves of the shelf system 104 are moveable to facilitate thepositioning of the shelves 104 relative to the magazine transport 108.FIG. 4A is a plan view of one embodiment of a movable-shelf layout forthe magazine-based data cartridge library 100. The embodiment comprisesa rotating shelf structure 166 with shelves 168A-D, a robot 170 thatcumulatively represents the magazine transport 108 and cartridgetransport 110, and one or more stationary drives 172. In operation, theshelf structure 166 is rotated, as indicated by the two-way arrow 171,to place one of the shelves 168A-D in the same plane as the robot 170 sothat the robot 170 can perform a magazine 101 or cartridge (not shown)transfer operation. In an alternative embodiment, one or more drives arealso associated with the rotating shelf structure 166. FIG. 4B is a planview of another embodiment of a movable-shelf layout for themagazine-based library 100 that includes movable drives 176A-D. Elementscommon to this embodiment and the embodiment in FIG. 4A have been giventhe same reference numbers. The embodiment shown in FIG. 4B comprisesthe further element of a rotating drive structure 174 that is capable ofholding multiple drives 176A-D. As illustrated herein, a drive, such as176C, can be rotated, as shown by the two-way arrow 173, into a positioncapable of cooperating with the robot 170 to transfer a data cartridge(not shown) between the drive 176C and the robot 170. In otherembodiments, one or more drives are associated with the rotating shelfstructure 166 and/or one or more shelves 168A-D are associated with therotating drive structure 174. Although not illustrated, another possiblelayout for the magazine-based data cartridge library 100 ismovable-drive type that is comprised of a stationary shelf system, suchas the shelf/shelves 130 of FIG. 2A, and movable drives, such as therotating drive structure 174 of FIG. 4B, for example. It should beappreciated that each of the embodiments of FIGS. 4A and 4B comprise atleast one drive, such as drive 172 of FIG. 4A. Further, each embodimentof FIGS. 4A and 4B comprise at least one shelf, such as the shelf 168A,capable of supporting two or more magazines 101 or multiple shelves,such as 168A-D, that cumulatively support two or more magazines 101.Moreover, while the illustrate embodiments contemplate that the rotatingelements rotate about a vertical axis, rotation about a horizontal axisis also feasible. It should also be appreciated that, while the robot170 cumulatively represents the magazine transport 108 and cartridgetransport 110, the magazine transport 108 and the cartridge transport110 may share one or more elements or be entirely separate from oneanother. It should be further appreciated that there may be othermovable-shelf layouts for the magazine-based data cartridge library 100of cooperating with a magazine transport 108.

The magazine-based data cartridge library 100 is also capable of beingimplemented in a layout that is a combination of two or more of therectilinear type, circular type, movable-shelf type, and movable-drivetype layouts.

FIG. 5A illustrates a typical drive 180 that is employed in themagazine-based data cartridge library 100. The drive 180 is capable ofwriting data to and/or reading data from a recording medium that islocated within a cartridge 224, shown in FIGS. 9A-B. Typically, thedrive 180 is capable of both writing data to and reading data from arecording medium located in the library 100. The drive 180 is comprisedof a housing 182 with a front surface 184 that has a receptacle 186 forreceiving a cartridge 224. The housing 182 further comprises a backsurface 187 and side surface 188 that is comprised of a first surface190A, a second surface (not shown) that is substantially parallel to thefirst surface, a third surface 190B that is substantially perpendicularto the first surface 190A, and a fourth surface (not shown) that issubstantially parallel to the third surface 190B. Typically, the drive180 is situated in the library 100 such that the first surface 190A liesin a horizontal plane or in a vertical plane. When the receptacle 186 islonger in one dimension than the other and extends in a direction thatis substantially parallel to the first surface 190A, these orientationsresult in the long dimension of the receptacle 186 extending eitherhorizontally or vertically. FIG. 5B illustrates the drive 180 with anorientation in which the long dimension of the receptacle 186 extendshorizontally. In a circular/cylindrical type implementation, either ahorizontal receptacle center line 192 or a horizontal drive center line194 of the drive 180 is typically located: (a) substantially along aradial line/plane, such as radial line 150A of FIG. 3A for example, (b)substantially along a line/plane that is parallel to a radialline/plane, or (b) along a line that is tangent to a circular arc, suchas tangent line 158 of FIG. 3C. FIG. 5C illustrates the drive 180 in anorientation in which the long dimension of the receptacle 186 extendsvertically. In a circular/cylindrical type implementation, either avertical receptacle center line 196 or a vertical drive center line 198of the drive 180 is typically located: (a) substantially along a radialline/plane, (b) substantially along a line/plane that is parallel to aradial line/plane, or (b) along a line that is tangent to a circulararc.

It should be appreciated that the magazine-based data cartridge library100 is capable of being adapted to any type of drive 106 that is capableof writing date to and/or reading data from a recording medium locatedin a cartridge. Concomitantly, the magazine-based data cartridge library100 is also adaptable to any type of data cartridge. For example, thelibrary 100 is capable of being applied to a cartridge with a recordingmedium that is either a disk, a tape, or a non-moving recording medium(e.g., a solid state memory). Further, the library 100 is capable ofbeing applied to cartridge with a recording medium that is magnetic,optical, magneto-optical or any other type of recording medium. Themagazine-based data cartridge library 100 is further capable of beingadapted for use with recording mediums that are not located in acartridge, e.g., CDs.

In many cases, the magazine-based data cartridge library 100 operates onmagazine 101 that, unlike the magazines 101 used in cartridge-based datacartridge libraries 100, comprises a structure that allows the magazine101 to be engaged by the magazine transport 108 so that the transport108 can move the magazine 101 within the library 100.

With reference to FIGS. 6A-6C, 7A-7B and 8A-8B, an embodiment of amagazine-based data cartridge library 202 (hereinafter referred to aslibrary 202) is described. Generally, the library 202 is comprised of:(a) an embodiment of a frame 204 for supporting elements of the library202; (b) an embodiment of an entry/exit port 206; (c) an embodiment of ashelf system 208; (d) an embodiment of drives 180; (e) an embodiment ofa magazine transport 212; (f) an embodiment of a cartridge transport214; (g) an embodiment of a power supply system 216; (h) an embodimentof a control system 218; and (i) an embodiment of fans 220 for coolingthe library 202. Unless otherwise specified, the LTO data cartridge 224adapted for use with the LTO magazine 270 will be used hereingenerically for illustrative purposes.

Before describing the library 202 in greater detail, the data cartridges224, as shown in FIG. 8B, and magazines 270, as shown in FIG. 7A, thatthe library 202 is adapted to manipulate are described. The library 202is adapted for operating on magnetic tape cartridges 224 and magazines270 that contain the tape cartridges 224. Specifically, the library 202is adapted for operating on cartridges 224 that conform to the followingcartridge formats: (a) LTO (linear tape open), (b) SAIT (super advancedintelligent tape, and (c) DLT (digital linear tape). Typically, thelibrary 202 is only used to store magazines 270 that are each used tohold cartridges 224 with the same cartridge format. For instance, thelibrary 202 may be used to store magazines 270 that are each used tohold LTO tape cartridges 224. However, the library 202 is capable ofstoring magazines 270 that are used to hold cartridges 224 of differenttypes. For instance, the library 202 is capable of storing a magazine270 that holds LTO tape cartridges 224 and another magazine 320, shownin FIG. 14A, that holds DLT tapes 254, shown in FIG. 11A. Typically, thelibrary 202 is used to store a magazine 270 where the magazine 270 isonly used to hold tape cartridges 224 that conform to a single format.For instance, the library 202 may be used to store a magazine 270 thatis only used to hold LTO tape cartridges. However, the library 202 iscapable of storing a magazine 270 that is used to hold cartridges 224 ofdifferent formats. For instance, the library 202 is capable of storing amagazine 270 that is used to hold LTO and SAIT tape cartridges 224, 240.

With reference to FIGS. 9A-9B, an LTO tape cartridge 224 comprises afirst cartridge face 226A, a second cartridge face 226B, a firstcartridge side 228A, a second cartridge side 228B, a first cartridge end230A, and a second cartridge end 230B. The distance between the firstand second cartridge faces 226A, 226B defines the height of the LTO tapecartridge 224, which is 0.85 in. The distance between the first andsecond side surfaces 228A, 228B defines the width of the LTO tapecartridge 224, which is 4.15 in. The distance between the first andsecond ends 230A, 230B defines the depth of the LTO tape cartridge 224,which is 4.02 in. The LTO tape cartridge 224 further comprises anorientation feature 232 that provides a basis for properly orientatingthe cartridge 224 for insertion in to an LTO tape drive (not shown) sothat data can be read from and/or written to the recording medium withinthe cartridge 224. The orientation feature 232 also provides a basis fororienting all of the LTO tape cartridges 224 stored in a particularmagazine, such as the magazine 270 of FIG. 7A, in the same manner. Thecartridge 224 also comprises a first pair of gripper notches 234A, 234Band a second pair of gripper notches 236A, 236B, with one or both pairof notches typically used by a device (not shown) that grips thecartridge 224 during transport between a magazine 270 and a drive, suchas the drive/s 180 of FIG. 7B.

With reference to FIGS. 10A-10B, a SAIT tape cartridge 240 comprises afirst cartridge face 242A, a second cartridge face 242B, a firstcartridge side 244A, a second cartridge side 244B, a first cartridge end246A, and a second cartridge end 246B. The distance between the firstand second cartridge faces 242A, 242B defines the height of thecartridge 240, which is 0.85 in. The distance between the first andsecond side surfaces 244A, 244B defines the width of the cartridge 240,which is 4.15 in. The distance between the first and second ends 246A,246B defines the depth of the cartridge 240, which is 4.02 in. Thecartridge 240 further comprises an orientation feature 248 that providesa basis for properly orientating the cartridge 240 for insertion in toan SAIT tape drive (not shown) so that data can be read from and/orwritten to the recording medium within the cartridge 240. Theorientation feature 248 also provides a basis for orienting all of theSAIT tape cartridges 240 stored in a particular magazine, such as themagazine 270 of FIG. 7A, in the same manner. The cartridge 240 alsocomprises a pair of gripper notches 250A, 250B, which are typically usedby a device (not shown) that grips the cartridge 240 during transportbetween a magazine 270 and a drive, such as the drive/s 180 of FIG. 7B.

With reference to FIGS. 11A-11B, a DLT tape cartridge 254 comprises afirst cartridge face 256A, a second cartridge face 256B, a firstcartridge side 258A, a second cartridge side 258B, a first cartridge end260A, and a second cartridge end 260B. The distance between the firstand second cartridge faces 256A, 256B defines the height of thecartridge 254, which is 1.00 in. The distance between the first andsecond side surfaces 258A, 258B defines the width of the cartridge 254,which is 4.15 in. The distance between the first and second ends 260A,260B defines the depth of the cartridge 254, which is 4.16 in. Thecartridge 254 further comprises an orientation feature 262 that providesa basis for properly orientating the cartridge 254 for insertion into aDLT tape drive (not shown) so that data can be read from and/or writtento the recording medium within the cartridge 254. The orientationfeature in an actual DLT cartridge 254 is somewhat more complex than thefeature shown in FIG. 11A. The orientation feature 262 also provides abasis for orienting all of the DLT tape cartridges 254 stored in aparticular magazine, such as the magazine 270 of FIG. 7A, in the samemanner. The cartridge 254 also comprises a single gripper notch 264,which is typically used by a device (not shown) that grips the cartridge254 during transport between a magazine 270 and a drive, such as thedrive/s 180 of FIG. 7B. The DLT tape cartridge 254 further comprises arecess 266 in the first end 260A that is typically used for to hold alabel, such as a bar-code label, that is used to identify the cartridge254.

Generally, as will be further elaborated in the description of FIGS.12A-12D, a magazine, such as an LTO/SAIT accommodating magazine 270, isadapted to hold multiple cartridges, such as LTO and/or SAIT tapecartridges 224 and 240 from FIGS. 11A and 11B for example. Themagazine-based library 202 of FIGS. 6A-6C, 7A-7B and 8A-8B will be usedfor illustrative purposes herein. The magazine 270 is adapted to bemoved within the library 202 by the magazine transport 212. Anengagement structure (not shown) adapted to cooperate with the magazinetransport 212 is capable of displacing the magazine 270 towards and awayfrom a shelf system 208 adapted to support the magazine 270 for archivalpurposes within the library 202. A magazine, such as the magazine 270,can be an open box like structure, such as a shoe box without a top,with partitions adapted to accommodate a specific cartridge form factor,such as a DLT 254 or LTO 224 form factor. On one embodiment, themagazine 270 is adapted to accommodate a single row of cartridges, suchas an LTO 224 cartridge 224. In yet another embodiment, the magazine 270can be arranged to accommodate two or more rows of cartridges.

Generally, the magazines employed within the library 202 are designed sothat when a magazine 270 is operatively situated in the library 202, anytape cartridges 224 held by the magazine 270 are oriented such that theface of the cartridge with the greatest surface area, such as the firstcartridge face 256A of DLT tape cartridge 254 from FIG. 11A, lies in avertical plane.

With reference to FIGS. 12A-12D, an embodiment of an LTO/SAIT magazine270 that is capable of accommodating LTO and/or SAIT tape cartridges 224and 240 is described. The magazine 270 comprises: (a) a closed-loop sidesurface 272 that is comprised of a first and second end sides 274A,274B, and first and second lateral sides 276A, 276B; (b) a bottom side278; (c) a top side 271; and (d) a plurality of partitioning elements280 that divide a space defined by the side surface 272 and bottom side278 into ten slots. The first and second end sides 274A, 274B, and thefirst and second lateral sides 276A, 276B extend between the bottom side278 and an edge 282 that defines the opening through which cartridges,such as the LTO cartridges 224, are inserted into and extracted from themagazine 270. Associated with each slot is an orientation structure 284that is used to ensure that all of the LTO and/or SAIT cartridges 224and 240 held by the magazine 270 have a predetermined orientation. FIGS.13A and 13B respectively illustrate the interaction of the orientationfeature 232 of an LTO cartridge 224 with the orientation structure 284and the orientation feature 248 of the SAIT cartridge 240 with theorientation structure 284. Also associated with each slot are first pairof stand-offs 286A, 286B and a second pair of stand-offs 288A, 288B thatposition the notches, such as 234A or 250A, of either an LTO or SAITtape cartridge 224 and 240 at a distance from the bottom side 278 thatis substantially the same as the distance between the bottom surface ofa DLT tape cartridge magazine 320, as shown in FIG. 14A, and the notch264 of a DLT cartridge 254 held therein. Consequently, regardless ofwhether an LTO, SAIT or DLT tape cartridge 224, 240 or 254 is presentedto the cartridge transport 214, the respective notch or notches, such as234A and 236A from the LTO cartridge 224, of the cartridge are atsubstantially the same distance from the bottom 278 of the magazine 270or 320. This simplifies the design of the cartridge transport 214. Thedistance between the first and second end sides 274A, 274B isapproximately equal to the distance between the front and backs surfacesof an LTO or SAIT drive (generically shown in FIG. 5A as front surface184 and back surface 187 of a generic drive), i.e., within about 20% ofthe distance between the front and back surface of such a drive.

Associated with the first end side 274A of the magazine 270 is a recess290A for accommodating a label that is used to identify the magazine 270or distinguish the magazine 270 from other magazines in the library 202.A recess 290B for accommodating an adhesive label is also associatedwith the second end side 274B. The recesses 290A and 290B are associatedwith the first and second end surfaces 274A and 274B because, when themagazine 270 is operatively positioned on a shelf of the shelf system208 in the library 202, either the first end side 274A or the second endside 274B will be exposed or visible so that any label residing in therecess 290A and 290B can be read. One alternative to the use of a recess290A and 290B adapted to hold an adhesive label is a sleeve or slotstructure capable of holding a non-adhesive label. Another alternativeto the use of a recess is a radio frequency identification tag (RFIDtag). An RFID tag can either be substantially permanently fixed to themagazine 270 or removable. Further, the RFID tag can either have apermanent identification code or be programmable. Moreover, the RFIDtag, unlike a bar-code label, does not necessarily require anunobstructed “line of sight” with a RFID tag reader to be read.Consequently, a single RFID tag may be sufficient.

The magazine 270 further comprises a first and second rails 292A, 292Bthat are respectively associated with the first and second lateral sides276A, 276B. The LTO data cartridge 224 will be used generically hereinfor purposes of illustration unless otherwise specified. With referenceto FIG. 12C, the first and second rails 292A, 292B are located so as toestablish an asymmetry that is used to position the magazine 270 with apredetermined orientation within the library 202. More specifically, thefirst and second rails 292A, 292B are asymmetric with respect to a plane294 that bisects the magazine 270. The ability to position the magazine270 with a predetermined orientation within the library 202 and toposition the cartridges 224 held by the magazine 270 with apredetermined orientation, in turn, substantially ensures that thecartridges 224 will also be presented to the cartridge transport 214 inthe same orientation. Other structures that establish an asymmetryrelative to other planes are also feasible. The rails 292A, 292B alsofacilitate the guiding of the magazine 270 within the library 202 (e.g.,guiding the magazine 270 to a particular location on a shelf of theshelf system 208) and prevent the magazine 270 from being displaced incertain directions. Respectively associated with the rails 292A, 292Bare notches 295A, 295B. The notches 295A, 295B are used withcomplementary structures associated with the magazine transport 212 tohold the magazine 270 in place when the magazine 270 is associated withthe transport 214. With reference to FIG. 12D, associated with thebottom side 278 of the magazine 270 are a pair of detents 296A, 296Bthat cooperate with complementary structures associated with a shelf ofthe shelf system 208 to prevent the magazine 270 from being displacedaway from a shelf of the shelf system 208 in an uncontrolled manner,i.e., being displaced away from the shelf by something other than themagazine transport 212. The detents 296A, 296B and the complementarystructures associated with a shelf of the shelf system 208 form apassive latch (i.e., a latch without any moving parts). A latch can alsobe realized by swapping the detents 296A, 296B and the complementarystructures, i.e., associating the detents 296A, 296B with the shelf ofthe shelf system 208 and the complementary structures (such as thereceptacle 530 comprised by the cleat 522A as shown in FIG. 22B with themagazine 270. Also feasible is an active latch in which either anelement associated with the magazine 270 or an element associated withthe shelf of the shelf system 208 includes a moving component.Typically, the moving element comprises an element that operates in aspring-like fashion to allow the latch to be engaged and disengaged whendesired. An example of an active latch mechanism is disclosed in U.S.patent application Publication Ser. No. 2003/0,076,618 A1.

The magazine 270 further comprises a first pair of engagement holes298A, 298B that are utilized by the magazine transport 212 to displacethe magazine 270 towards or away from a shelf in the shelf system 208.More specifically, the magazine transport 212 “hooks” the holes 298A,298B and then pulls and/or pushes the magazine 270 towards or away froma shelf in the shelf system 208. Associated with the first pair ofengagement holes 298A, 298B is a first engagement flag structure 300that is comprised of a pair of holes 302A, 302B, that are separated by abar 304. The engagement flag structure 300 operates such that whenmagazine transport 212 has engaged the magazine 270, the bar 304 breaksa beam of light and when the magazine transport 212 is not engaging themagazine 270, the bar 304 does not break the beam of light. As analternative to the engagement flag structure 300, the exterior surfaceof the bottom side 278 of the magazine 270 can be used to indicate whenthe magazine transport 212 is engaging the magazine 270 and when themagazine transport 212 is not engaging the magazine 270. To elaborate,the bottom side 278 can be used as a reflective surface that can be usedto determine whether or not the magazine 270 has been engaged by themagazine transport 212.

The magazine 270 further comprises a second pair of engagement holes306A, 306B, and a second engagement flag structure 308 that are used inthe same manner as the first pair of engagement holes 298A, 298B and thefirst engagement flag structure 300. Two sets of engagement holes 298A,298B, 306A, 306B are utilized because when the magazine 270 isassociated with a shelf in the shelf system 208 on one side of themagazine transport 212, the first pair of engagement holes 298A, 298B isaccessible but the second pair of engagement holes 306A, 306B is notreadily accessible. Conversely, when the magazine 270 is associated witha shelf in the shelf system 208 that is located on the opposite side ofthe magazine transport 212, the second pair of engagement holes 306A,306B is accessible but the first pair of engagement holes 298A, 298B isnot readily accessible. Presently, the magazine 270 has a third pair ofengagement holes 310A, 310B with an associated third engagement flagstructure 312 and a fourth pair of engagement holes 314A, 314B and anassociated fourth engagement flag structure 316 that are capable ofbeing used by the magazine transport 212 to move the magazine 270 butare not currently utilized. It should be appreciated that otherstructures that are capable of being “hooked” are feasible. Forinstance, a single hole is feasible. Also, feasible are one or multipleindentations and one or multiple protrusions. Further, while themagazine transport 212 “hooks” the magazine 270, it should beappreciated that the magazine 270 can be adapted to facilitateengagement of the magazine 270 by a device that grasps the magazine 270between two arms. Possible structures to facilitate grasping of themagazine 270 comprise a pair of holes in the magazine 270, a pair ofindentations in the magazine 270, and a pair of protrusions that extendoutward from one or more surfaces of the magazine 270.

With reference to FIGS. 14A-14B, an embodiment of a DLT magazine 320that is capable of accommodating DLT tape cartridges 254 is described.The DLT magazine 320 is substantially identical to the LTO/SAIT magazine270. Consequently, those elements of the DLT magazine 320 that arecommon to both the DLT magazine 320 and LTO/SAIT 270 are not describedfurther. Further, in describing the DLT magazine 320, elements of theDLT magazine 320 that are substantially identical to elements in theLTO/SAIT magazine 270 will bear the same reference number as thosesubstantially identical elements in the LTO/SAIT magazine 270. The DLTmagazine 320, in addition to the elements that are common to theLTO/SAIT magazine 270, comprises partitioning elements 322 that dividethe interior space of the magazine into nine slots 277. Associated witheach slot 277 is an orientation structure 324 that is used to ensurethat all of the DLT cartridges 254 held by the magazine 320 have apredetermined orientation. FIG. 15 illustrates the interaction of theorientation feature 262 of a DLT cartridge 254 with the orientationfeature 324 of the magazine 320. It should also be noted that the DLTmagazine 320 does not employ any stand-offs.

Having described the cartridges 224, 240 or 254 and magazines 270 and320 on which the library 202 operates, the general layout of the library202 is now described. As shown in FIG. 16, the layout of the library 202is a rectilinear layout that conforms to the specifications for therectilinear layout illustrated in FIG. 2B. More specifically, the shelfsystem 208 comprises five columns of shelving 328A located along a firstplane 330A, two columns of shelving 328B located along a second plane330B, and two columns of drives 332 located along the second plane 330B.The magazine transport 212 and cartridge transport 214 are each locatedin the space between the first and second planes 330A, 330B and each 212and 214 move at least within a portion of the space between the firstand second planes 330A, 330B. Most of the other elements of the library202 also conform to the rectilinear layout. Specifically, the entry/exitport 206 is located within the five columns of shelving 328A and alongthe first plane 330A; the power supply 216 is located below the twocolumns of drives 332 and either along the second plane 330B or along aparallel plane; the control system 218 is located below the two columnsof shelving 328B and either along the second plane 330B or along aparallel plane; and the fans 220 are located under the five columns ofshelving 328A and either along the first plane 330A or a parallel plane.

In addition to the general layout of the library 202, the user has achoice about the function of certain space in the library 202. Toelaborate and with reference to FIG. 7B, the library 202 comprises auser-definable space 332 with six stations that are each capable ofaccommodating either one of two types of modules. As shown inconjunction with FIG. 23B, each of the stations is capable ofaccommodating a drive bay module 540, that holds up to four drives, suchas 548A-D, or a magazine bay module that provides shelving for up tofour magazines 270. A user-definable space with less than six stationsis feasible. Further, if multiple stations are employed, each stationdoes not need to have the same dimensions. For instance, a station couldaccommodate either only one drive 180 or provide shelving for only onemagazine 270.

With reference to FIGS. 6A-6C, 7A-7B and 8A, 8B, the frame 204 compriseselements that define the edges of a box-like structure and the surfacesof the box-like structure, [therein defining an interior space]. Thesurfaces comprise a front surface 340A, a back surface 340B, a firstside surface 340C, a second side surface 340D, a top surface 340E, and abottom surface 340F. Associated with the front surface 340A are theentry/exit port 206, an operator interface 342 that is implemented witha touch screen, and a grill structure 344 that covers the fans 220.Associated with the back surface 340B are a fixed panel 346 that islocated adjacent to a series of shelves 208, a hinged door panel 348that provides access to the drives 180 and the power supply 216, anopening 350 through which an AC cable(s) is/are connected to the powersupply 216, and a grill 352 for promoting air circulation within thelibrary 202. The first side surface 340C is removable so that thelibrary 202 can be cascaded with at least one add-on unit to expand thelibrary 202. Also associated with the first side surface 340C is a firstclear panel 354A that allows an operator to view the interior of thelibrary 202. Similarly, a second clear panel 354B is associated with thesecond side surface 340D. The top surface 340E includes a pair ofknockouts 356A, 356B that can be used to receive one or more AC cablesthat are connected to the power supply 216 and/or one or more computercables that are used to connect the library 202 to a host computer. Alsoassociated with the top surface 340E is a fire suppression system hole358 for receiving a nozzle or other device for dispensing a fireretardant into the library 202. Associated with the bottom surface 340Fare casters 360A, 360B, 360C and 360D that facilitate movement of thelibrary 202 and adjustable stands 362A, 362B, 362C and 362D that allowthe library 202 to be leveled after the library 202 has been positionedin a relatively permanent location. Further associated with the bottomsurface 340F are openings 364A, 364B for receiving one or more AC cablesthat are connected to the power supply 216 and/or a computer cable(s)that are used to connect the library 202 to a host computer.

The library 202 has a depth of 43.16 in. as measured from the frontsurface 340A to the back surface 340B, a width of 30.50 in. as measuredfrom the first side surface 340C to the second side surface; and aheight of 74.25 in. as measured from the top surface 340E to the bottomsurface 340F.

Generally, the entry/exit port 206 serves to move magazines 270 between:(a) an environment that is exterior to the library 202 and accessible toa user, or operator; and (b) a space located within the library 202 andaccessible by the magazine transport 212. When the entry/exit port 206is exposed to the exterior environment such that an operator can eitherremove a magazine 270 that has been conveyed from the space within thelibrary 202 or place a magazine 270 in the entry/exit port 206 forconveyance to the space within the library 202, the port 206 is in afirst state. Similarly, when the port 206 is exposed to the spacelocated within the library 202 such that the magazine transport 212 caneither remove a magazine 270 that is in the space or place a magazine270 in the space (typically, for conveyance to the exterior environment)the magazine 270 is in a second state.

With reference to FIGS. 17A and 17B, the entry/exit port 206 iscomprised of a first entry/exit port 368 and a second entry/exit port370 that operates independently of the first entry/exit port 368. Thefirst and second entry/exit ports 368, 370 provide greater throughputthan a single entry/exit port, i.e., more magazines 270 can be movedbetween the exterior environment and the spaces within the library 202associated with the first and second entry/exit ports 368, 370 over agiven time period than is possible with a single exit/entry port of thesame design. In addition, the first and second entry ports 368, 370provide redundancy. Consequently, if one of the first and secondentry/exit ports 368, 370 should become disabled, the other port can, inmany cases, still be used to transport magazines 270. A library 202 witha single entry/exit port is also practicable. With continuing referenceto FIGS. 17A and 17B, the entry exit port 206 comprises a chassis 372with an exterior side 374A that is exposed to the exterior environmentor adjacent to the front side 340A and an interior side 374B that isexposed to the magazine transport 212 and is substantially located alongthe plane 330A. In the illustrated embodiment, the first entry/exit port368 is in the second state, i.e., a magazine 270 can be removed from aspace 378 by the magazine transport 212 or a magazine 270 (assumingmagazine 270 is no longer present in the space) can be inserted into thespace 378 by the magazine transport 212. Conversely, the secondentry/exit port 370 is in the first state, i.e., an operator can removea magazine 270 from the port 370 or an operator can associate a magazine270 (assuming magazine 270 is no longer present) with the port 370 fortransport to the space 382.

The first entry/exit port 368 is substantially identical to the secondentry/exit port 370. Consequently, the first entry/exit port 368 isdescribed with the understanding that the description is also applicableto the second entry/exit port 370. Generally, the first entry/exit port368 utilizes a support, such as the tray 386 of FIG. 18A, to move amagazine 270 between: (a) a first location at which an operator caneither associate a magazine 270 with the support or remove a magazine270 from the support; and (b) a second location at the magazinetransport 212 can either remove a magazine 270 from the support orassociate a magazine 270 with the support. Further, the first entry/exitport 368 also utilizes a door system for preventing an operator fromaccessing the interior of the library 202 and possibly getting injuredby one of the moving elements. The door system is comprised of aninterior door 430B and an exterior door 430A (as shown in FIG. 18D). Thedoor system operates such that when the support is in the firstlocation, shown in FIG. 17A, such that an operator can either associatea magazine 270 with the support or remove a magazine 270 from thesupport, the exterior door 430A is open and the interior door 430B isclosed or closing to prevent the operator from accessing the interior ofthe library 202. Conversely, when the support is in the second location(as shown in FIG. 17B), such that the magazine transport 212 can eitherassociate a magazine 270 with the support or remove a magazine 270 fromthe support, the interior door 430B is open to provide the magazinetransport 212 with access to the support and the exterior door 430A isclosed or closing to prevent an operator from accessing the interior ofthe library 202.

With reference to FIGS. 18A-18E, the first entry/exit port 368 isgenerally comprised of: (a) a tray 386 for supporting a magazine 270;(b) a door assembly 388 that comprises an exterior door 430A and aninterior door 430B, is attached to the chassis 372, and used to supportthe tray 386; and (c) an actuator system 390 for moving the tray 386,the exterior door 430A, and the interior door 430B.

The tray 386 is comprised of a bottom side 392, first and second sidewalls 394A, 394B, an exterior end wall 396 and a movable end wall 398.The bottom side 392, first and second side walls 394A, 394B and exteriorend wall 396 define a shallow interior space for supporting a magazine270. The first and second side walls 394A, 394B prevent the magazine 270from moving laterally. The movable end wall 398 prevents a magazine 270from moving in the direction of movable end wall 398 under certainconditions but permits a magazine 270 to move in the direction of themovable end wall 398 under other circumstances. To elaborate, themovable end wall 398 is moveable between a first position and a secondposition. In the first position, the movable end wall 398 prevents amagazine 270 that is located in the interior space from moving in thedirection of the movable wall 398. The movable end wall 398 performsthis preventive function when the tray 386 is moving between the firstlocation and the second location, e.g., when a magazine 270 is beinginserted into the library 202 from the exterior environment. In thissituation, the magazine 270 acquires momentum that, if the moveable endwall 398 were not in the first position, could potentially cause themagazine 270 to slide on the tray 386 and into the space in which themagazine transport 212 and cartridge transport 214 operate, potentiallydamaging the library 202. In the second position, the movable end wall398 allows the magazine transport device 212 to either place a magazine270 on the tray 386 or remove a magazine 270 from the tray 386. Themovable end wall 398 is placed in the second position after the tray 386has been moved to the second location, i.e., the location at which themagazine transporter 212 is able to either load the tray 386 with amagazine 270 or remove a magazine 270 from the tray 386, or at a timebefore the tray 386 has reached the second location but at which it isunlikely that any momentum imparted to the magazine 270 is likely tocarry the magazine 270 into the magazine transporter 212 or cartridgetransport 214 operational space.

Associated with the bottom side 392 of the tray 386 is a linear rail 400that mates with a rail block located on the door assembly 388 to allowthe tray 386 to slide between the first and second locations. Alsoassociated with the bottom side 392 is a sensor assembly 402 that isused to sense the possible presence of a magazine 270 in the interiorspace of the tray 386 and a flex cable 404 that allow the signalsproduced by the sensor assembly 402 to be conveyed to the control system218. Further associated with the bottom side 392 is a pair of brackets406A, 406B to which the movable end wall 398 is mounted.

Associated with the first and second side walls 394A, 394B are guides408A, 408B that form part of a linkage that is used to move the exteriorand interior doors 430A, 430B between the open and closed positions. Afirst pair of end blocks 410A, 410B are located at the ends of theguides 408A, 408B that are located adjacent to the exterior end wall396. A second pair of end blocks 412A, 412B are located at the ends ofthe guides 408A, 408B that are located adjacent to the movable end wall398. A drive block 414 that is used to receive the motive forces fromthe actuator system 390 that cause the tray 386 to slide between thefirst and second locations is associated with the first side wall 394A.Also associated with the first side wall 394A is an orientation feature416 that is used in conjunction with the rails 292A, 292B of a magazine270 to substantially ensure that a magazine 270 that an operator placesin the interior space of the tray 386 has a desired orientation. Toelaborate, if an operator places a magazine 270 in the interior space ofthe tray 386 with magazine 270 oriented such that the rails 292A isdisposed adjacent to the orientation feature 416, the magazine 270 isproperly oriented and the bottom side 278 of the magazine 270 lies flushwith the bottom side 392 of the tray 386. If, however, an operatorplaces a magazine 270 in the interior space of the tray 386 with themagazine 270 oriented such that the rail 292B is disposed adjacent tothe orientation feature 416, the magazine 270 is not properly orientedand the bottom side 278 of the magazine 270 will not lie flush with thebottom side 392 of the tray 386. Further, the sensors associated withthe sensor assembly 402 are able to detect this condition and providethe control system 218 with this information so that the control system218 can prevent the tray 386 from being moved until the magazine 270 isproperly oriented. In one embodiment, the sensor assembly 402 comprisestwo optical sensors that are disposed laterally across the tray 386.Another sensor is operatively attached to the chassis 372 adjacent tothe exterior door 430A and operates to sense the presence of an objectadjacent to the door 430A. The signals produced by the two opticalsensors and the door sensor are capable of being used to determine if amagazine 270 is not present in the tray 386, if a properly loadedmagazine 270 is present in the tray 386, an improperly loaded magazine270 is present in the tray 386, or something other than a magazine 270is present in or adjacent to the tray 386.

Associated with the exterior end wall 396 is a sloped surface 418 thatfacilitates insertion of a magazine 270 into the interior space of thetray 386 when the tray 386 is in the first location. The sloped surface418 terminates before reaching the bottom side 392 so that a corner 419is formed for receiving the corner formed by the end side 274A andbottom side 278 of a magazine 270. Further, when the movable end wall398 is in the first position and a magazine 270 is in the interior spaceof the tray 386, the magazine 270 is clamped between the corner 419 andthe movable end wall 398.

The movable end wall 398 is comprised of an S-shaped member 420 that ispivotally attached to the brackets 406A, 406B. A spring (not shown)biases the S-shaped member 420 so that the S-shaped member 420 is in thefirst position, as shown in FIG. 18C, to prevent a magazine 270 fromentering the operational space of the magazine transport 212 andcartridge transport 214 in an uncontrolled fashion. The S-shaped member420 further comprises a camming surfaces 424A, 424B that cooperate withcamming elements associated with the door assembly 388 to move theS-shaped member 420 into the second position, shown in FIG. 19E, so thatthe magazine transport 212 can either remove a magazine 270 from thetray 386 or associate a magazine 270 with the tray 386.

With reference to FIG. 18D, the door assembly 388 comprises a doormounting plate 428, exterior door 430A, and an interior door 430B. Theexterior door 430A is pivotally connected to the door mounting plate 428via mounting blocks 432A, 432B, which constrain the exterior door 430Ato rotate about a horizontal axis. The exterior door 430A comprisesfirst and second connection flanges 434A, 434B for establishing pivotalconnections with a linkage that is used to move the door 430A.Similarly, the interior door 430B is pivotally connected to the doormounting plate 428 via mounting blocks 436A, 436B, which constrain theinterior door 430B to rotate about a horizontal axis. The interior door430B comprises first and second connection flanges 438A, 438B forestablishing pivotal connections with a linkage that is used to move thedoor 430B. Also comprising the door assembly 388 is a rail block 440that cooperates with the linear rail 400 of the tray 386 to allow thetray 386 to slide between the first and second locations. The doorassembly 388 further comprises a pair of cam elements 442A, 442B thatinteract with a camming surfaces 424A, 424B associated with the movableend wall 398 to move the S-shaped member 420 to the second position sothat the magazine transport 412 can either remove a magazine 270 fromthe tray 386 or place a magazine 270 on the tray 386.

The actuator system 390 operates to move the tray 386 between the firstand second positions and to move the exterior and interior doors 430A,430B between open and closed positions. Moreover, the actuator system390 coordinates the opening and closing of the interior doors 430A, 430Bwith the movement of the tray 386 between the first and secondpositions. To elaborate, the actuator system 390 operates such thatduring the time that the tray 386 is moving from the first location tothe second location (e.g., when a magazine 270 is being inserted intothe library 202), the exterior door 430A moves between open and closedpositions and the interior door 430B moves between closed and openpositions. Conversely, the actuator system 390 operates such that duringthe time that the tray 386 is moving from the second location to thefirst location (e.g., when a magazine 270 is being extracted from thelibrary 202), the exterior door 430A moves between closed and openpositions and the interior door 430B moves between the open and closedpositions.

The actuator system 390 comprises a pair of brackets 446A, 446B thatsupport a lead screw 448, a nut 450 that is attached to the lead screw448 and has a post that engages a hole 415 in the drive block 414, anelectric motor 452, and a pair of gears 454A, 454B that transmit arotational force produced by the electric motor 452 to the lead screw448. Further comprising the actuator system 390 is a first pair ofslotted blocks 456A, 456B (see FIG. 19A) that are operatively associatedwith the guide 408A. A second pair of slotted blocks 458A, 458B that areoperatively associated with the guide 408B. The actuator system 390further comprises a first pair of links 460A, 460B that, respectively,pivotally connect the first connection flange 434A of the exterior door430A with the slotted block 456A and the first connection flange 438A ofthe interior door 430B with the slotted block 456B. Similarly, a secondpair of links 462A, 462B, respectively, pivotally connects the secondconnection flange 434B of the exterior door 430A with the slotted block458A and the second connection flange 438B of the interior door 430Bwith the slotted block 458B. The position of the tray 386 is provided bya detector that operates to detect the presence of a flag associatedwith the tray 386 when the tray 386 is at a home position and an encoderassociated with the motor 452. Other position detecting schemes arefeasible.

With reference to FIGS. 19A-19F, the operation of the entry/exit port368 in moving a magazine 270 between an environment in which the tray386 is accessible by an operator to a space that is accessible to themagazine transport 212 (i.e., in direction 468) is described.

With reference to FIG. 19A, the entry/exit port 368 is in the firststate, i.e., the tray 386 is at a location at which an operator canassociate a magazine 270 with the tray 386. For illustration, themagazine 270 has been associated with the tray 386. In this regard, thespring associated with the movable end wall 398 has placed the S-shapedmember 420 in the first position. As a consequence, the magazine 270 isprevented from sliding in the direction 468. Further, the magazine 270is clamped between the corner 419 and the S-shaped member 420. At thispoint, the exterior door 430A is open and the interior door 430B isclosed. Additionally, the slotted block 456B is either contacting therail end block 412A or very close to the rail end block 412A.

With reference to FIG. 19B, the actuator system 390 has begun to movethe tray 386 in the direction 468, the exterior door 430A is still openand the interior door 430B has moved from the closed position towardsthe open position. More specifically, the electric motor 452 has beenused to produce a rotational force that has been transmitted by the pairof gears 454A, 454B to the lead screw 448. The rotation of the leadscrew 448 has caused the nut 450 to move towards the electric motor 452.The nut 450, in turn, has applied a force to the tray 386 via the driveblock 414 that has caused the tray 386 to slide over the rail block 440and towards the electric motor 452. As the tray 386 has moved towardsthe electric motor 452, either gravity or contact with the tray 386 hascaused the interior door 430B to begin rotating towards the openposition. However, interaction between the rail end block 412A and theslotted block 456B, which is connected to the interior door via the link460B, has controlled the movement of the interior door 430B.

With reference to FIG. 19C, the actuator system 390 has continued tomove the tray 386 in the direction 468, the exterior door 430A is stillin the open position and the interior door 430B is now also in the openposition. More specifically, the electric motor 452 has continued tomove the tray 386 in the manner described with respect to FIG. 19B.Further, the interaction between the rail end block 412A and the slottedblock 456B has continued to control the movement of the interior door430B between the closed position and the open position.

With reference to FIG. 19D, the actuator system 390 has continued tomove the tray 386 in the direction 468, the exterior door 430A has nowbegun to move from the open position towards the closed position, andthe interior door 430B remains in the open position. More specifically,the electric motor 452 has continued to move the tray 386 in the mannerdescribed with respect to FIG. 19B. In addition, the movement of thetray 386 has caused the rail end block 410A to begin applying a motiveforce to the slotted block 456A. In turn, the slotted block 456A, due tothe connection with the exterior door 430A via the link 460A, has begunto cause the exterior door 430A to rotate towards the closed position.

With reference to FIG. 19E, the actuator system 390 has continued tomove the tray 386 in the direction 468, the exterior door 430A is now inthe closed position, the interior door 430B remains in the openposition, and the S-shaped member 420 has been moved to the secondposition so that the magazine transport 212 can engage the magazine 270.More specifically, the electric motor 452 has continued to move the tray386 in the manner described with respect to FIG. 19B. In addition, themovement of the tray 386 has caused the rail end block 410A to continueapplying a motive force to the slotted block 456A. In turn, the slottedblock 456A, due to the connection with the exterior door 430A via thelink 460A, has caused the exterior door 430A to rotate to the closedposition. In addition, the movement of the tray 386 has caused the camelements 442A, 442B to engage the camming surfaces 424A, 424B of theS-shaped member 420 and rotate the S-shaped member such that themagazine 270 can be removed from the tray 386 by the magazine transport212. At this point, the entry/exit port 368 is in the second state.

It should be appreciated by one skilled in the art that to extract amagazine 270 from the library 202 using the entry/exit port 368, thesequence of operations illustrated in FIGS. 19A-19E is reversed.

It should also be appreciated by one skilled in the art that theentry/exit port 368 is capable of being modified in a number of ways,provided a magazine 270 transport is provided that is able to place amagazine 270 in the port 368 or remove a magazine 270 from the port 368.The following sets forth some of these other embodiments. For example,the tray 386 is a support for a magazine 270 that primarily supports amagazine 270 from below. Depending upon the design of a magazine 270, asupport that contacts one or both of the sides 276A, 276B of a magazine270 or the top surface (not shown) of a magazine embodiment is feasible.Further, the tray 386 employs the orientation feature 416 tosubstantially ensure that magazine embodiments that employ theasymmetrical rails 292A, 292B are properly inserted into the tray 386.The entry/exit port 368 is capable of being adapted to magazineembodiments that employ a different orientation feature.

Additionally, structures other than the movable end wall 398 can beemployed to prevent undesired movement of a magazine 270. For instance,a device that clamps the side surface, such as side 276A, of themagazine 270 can be employed. If a particular magazine embodiment hastop and bottom surfaces, a device that clamps these surfaces is alsofeasible. Another alternative to preventing undesired movement of amagazine 270 is to provide a structure that engages a feature of themagazine 270, such as a hole, indentation or protrusion. Further, amovable end wall in which the magazine transport 212, rather than theentry/exit port 368, causes the wall to move between positions isfeasible.

Furthermore, while the actuation system 390 employs the electric motor452 and linkages to cause the tray 386, exterior door 430A and interiordoor 430B, to move in a coordinated fashion, other approaches arefeasible. For example in one embodiment, a system in which separateelectrical motors or other motive components (such as solenoids) areassociated with the magazine support, such as the tray 386 in oneembodiment, and each of the doors 430A, 430B is feasible. In this case,coordination of the movements of the tray 386 and the doors 430A, 430Bis achieved by controlling the motors or other motive components.Similarly, a system in which an electrical motor or other motivecomponent is associated with the magazine support and another motor ormotive component is associated with the combination of the two doors430A, 430B is feasible. In this case, the operation of the two doors430A, 430B is coordinated by a mechanical linkage extending between thedoors 430A, 430B, and the movements of the support and the doors 430A,430B is coordinated by appropriately controlling the motors or othermotive components. It should also be appreciated that designs employinglinear actuators (such as solenoids) are feasible. Further, otherapproaches for moving the magazine holder or support, such as abelt-and-pulley and rack-and-pinion systems, are feasible.

Additionally, while the entry/exit port 368 employs planar doors 430A,430B that each rotate about horizontal axes that are parallel to theplanes of the doors 430A, 430B, many other designs are feasible. Forexample, designs in which a door 430A, 430B rotates about an axis thatis parallel to the plane of the door 430A, 430B but not a horizontalaxis (e.g., a vertical axis) is feasible. Designs in which a door 430A,430B rotates about an axis that is substantially perpendicular to theplane of the door 430A, 430B are also feasible. An example of such adesign is shown in FIG. 20A. In this design, both an exterior door 472Aand an interior door 472B that resides in a plane that is substantiallyparallel to the plane of the exterior door 472A rotate about an axisthat is perpendicular to the planes of both of the doors 430A, 430B. Inaddition, the exterior door 472A and the interior door 472B areangularly or rotationally offset. Coordination of the opening andclosing of the doors 430A, 430B is achieved by a rod 474 that connectsthe doors 430A, 430B. It should be noted that with such a design, theexterior door 472A and the interior door 472B move simultaneously.Consequently, when one of the doors such as the exterior door 430A, ismoving from the open position to the closed position, the other door,such as the interior door 430B, is moving from the closed position tothe open position. Also feasible are designs in which a door embodimentis linearly translated between open and closed positions, rather thanrotated between open and closed positions. An example of such a designis shown in FIG. 20B. In this design, a door 476 is disposed between apair of guides 478A, 478B that constrain the door 476 to move linearlybetween open and closed positions. A linkage 480 is used to apply theforces needed to move the door 476 between open and closed positions. InFIG. 20B, the door 476 is in an open position so that a magazine 482 canpass through the door structure. Also feasible are door embodiments inwhich a door is comprised for two or more elements. An example of such adesign is shown in FIG. 20C. In this design, a door structure 484 iscomprised of a pair of doors 486A, 486B that are constrained to movelinearly by guides 488A, 488B. A linkage 490 is used to transmit theforces that cause the doors 486A, 486B to move: (a) towards each otherto achieve a closed position, and (b) away from each other to achieve anopen position. Further feasible are door embodiments that employnon-planar doors. An example of such a design is shown in FIG. 20D. Inthis design, a curved door 492 is constrained to rotate about an axis494 by a pair of curved guides 496A, 496B and a linkage 498. Alsofeasible is a “roll top” door embodiment. An example of door structurethat utilizes roll top doors is shown in FIG. 20E. In this embodiment, adoor structure 500 is comprised of a pair of roll-top doors 502A, 502Bthat are connected to one another by a flexible cable structure 504. Aguide structure 506 defines a track around which the doors 502A, 502B.This design also allows for overlap in the times during which one of thedoors, such as door 502A, is transitioning between an open position anda closed position and the other door, such as door 502B, istransitioning between a closed position and an open position.

While the entry/exit port 368 employs a movable tray 386, an entry/exitport embodiment that employs a cartridge holder embodiment that does notmove is also feasible.

An alternative embodiment to an entry/exit port 368 that employs a pairof doors, such as the interior and exterior doors 430A, 430B, is acarousel entry/exit port. An example of a carousel entry/exit port isshown in FIGS. 21A-21B. In this embodiment, a carousel entry/exit port508 is comprised of a housing 510 that defines a port 512 for holding amagazine 270. The housing 510 rotates about an axis 514. Rotation isaccomplished by an electric motor (not shown). In operation, thecarousel exit/entry port 508 rotates between a first location at whichan operator can either remove a magazine 270 from the port 512 orassociate a magazine 270 with the port 512 and a second location atwhich a magazine transport device, such as the magazine transport device212, can either remove a magazine 270 from the port 512 or associate amagazine 270 with the port 512.

Generally, the shelf system 208 serves to support magazines 270 in thelibrary 202 in a preferred or desired orientation. The shelf system 208orients magazines 270 in the library such that: (a) the magazines 270are parallel to one another: (b) any cartridges 224 contained in themagazines 270 are oriented to facilitate insertion and extraction by thecartridge transport 214; and (c) a high data density footprint isachieved. Furthermore, the shelf system 208, each of the shelvescomprising the shelf system 208 is capable of supporting multiplemagazines 270. However, a shelf system 208 with a shelf that is onlycapable of accommodating a single magazine 270 is feasible.

With reference to FIG. 16, the shelf system 208 is comprised of the fivecolumns of shelving 328A and the two columns of shelving 328B. Withreference to FIGS. 7A-7B and 8A-8B, the five columns of shelving 328Aare realized by ten, horizontally extending shelves that are eachcapable of supporting up to five magazines 270 and three, horizontallyextending shelves that are each capable of supporting up to threemagazines 270. The two columns of shelving 328B are realized by twelve,horizontally extending shelves that are each capable of supporting up totwo magazines 270.

FIG. 22A illustrates a shelf 518 that is capable of accommodating up tofive magazines 270. Shelf 518 is described with the understanding thatthe description is also applicable, with appropriate modifications, tothe shelves that are capable of accommodating different numbers ofmagazines 270, such as the shelves in the library 202 that are capableof accommodating up to three magazines 270 and up to two magazines 270.The shelf 518 comprises a planar member 520 for supporting magazines 270from underneath. The shelf 518 further comprises six cleats 522A-F thatserve a number of purposes. Specifically, the cleats 522A-F: (a) dividethe shelf 518 into five cells, each of which is capable of accommodatinga single magazine 270; (b) constrain any magazines 270 supported by theshelf 518 to be oriented substantially parallel to one another; (c)constrain any magazines 270 supported by the shelf 518 to be orientedsuch that any cartridges in the magazines 270 are all oriented in thesame manner to facilitate insertion and extraction of the cartridges 224by the cartridge transport 214; (d) prevent, due to the spacing betweenconsecutive cleats, lateral displacements (i.e., displacements along thex-axis) of any magazines 270 supported by the shelf 518; (e) preventvertical displacements (i.e., displacements along the z-axis) of anymagazines 270 supported by the shelf 518; (f) resist undesiredhorizontal displacements (i.e., displacements along the y-axis) of amagazine 270 supported by the shelf 518; (g) constrain the directionthat a magazine 270 is either moved towards the shelf 518 or away fromthe shelf 518 to horizontal displacements (i.e., displacements along they-axis).

With reference to FIG. 22B, the cleat 522A is described with theunderstanding that the description is also applicable to cleats 522B,522C, 522D, 522E and 522F. The cleat 522A is comprised of a dual guidestructure 524 with an upper guide 526A for receiving the rail 292A of amagazine 270 and a lower guide 526B for receiving the rail 292B of amagazine 270. The cleat 522A also comprises prongs 528A, 528B, 528C and528D that engage holes (not shown) in the planar member 520 and operateto hold the cleat 522A in place on the planar member 520. Additionally,the cleat 522A comprises a receptacle 530 (which also extends away fromthe side 524 of the cleat 522A not seen in FIG. 22B) for accommodatingone of the detents 296A, 296B associated with a magazine 270, and whenaccommodating one of the detents 296A, 296B, operating to resistundesired horizontal displacements of the magazine 270. The cleat 522Aalso comprises an end surface 532 that is detectable by the magazine 270transport 512 and facilitates positioning of the magazine transport 512relative to the shelf 512 and relative to a particular magazine 270supported by the shelf 512. The end surface 532 presently has areflective character that makes the end surface distinguishable from theadjacent features. A contrasting color approach is also feasible, aswell as a tactile approach.

FIG. 22C demonstrates the manner in which two cleats 522B and 522Ccooperate to achieve some of the previously noted purposes. Theoperation of cleats 522B and 522C on a magazine 270 is described withthe understanding that other pairs of cleats operate in a substantiallysimilar manner. The cleats 522B and 522C are spaced from one anothersuch that the upper guide 526A of cleat 522B captures the rail 292A ofthe magazine 270 and the lower guide 526B of the cleat 522C captures therail 292B of the magazine 270. As a consequence, the cleats 522B and522C cooperate to prevent the magazine 270 from being laterally andvertically displaced. Additionally, the cleats 522B, 522C limitdisplacements of the magazine 270 to horizontal displacements along they-axis. Although not shown in FIG. 22C, it should be appreciated thatthe detents 296A, 296B of the magazine 270 are respectively engaging thereceptacle 530 associated with the cleat 522B and the receptacle 530associated with the cleat 522C to prevent undesired horizontaldisplacements of the magazine 270. Further, the cleats 522B, 522C causethe magazine 270 to be oriented such that a cartridge 224 has aparticular orientation on the shelf 518 and within the library 202. Toelaborate, as previously noted, each magazine 270 has an orientationstructure associated with each slot that substantially ensures that allof the SAIT cartridges 240 stored by the magazine 270 have the sameorientation in the magazine 270. The rails of the magazines 292A, 292Bcooperate with the guides 526A, 526B associated with the pair of cleats522B, 522C to substantially ensure that the magazine 270 has aparticular orientation on the shelf 518. As a consequence, the guides526A, 526B also substantially ensure that the cartridge 240 has aparticular orientation on the shelf 518 and within the library 202.Further, since all of the cleats 522A-522F are oriented on the planarmember 520 in the same way, all of the magazines 270 supported by theplanar member 520 have the same orientation and all of the cartridges240 contained by all of the magazines 270 have the same orientation, asshown in FIG. 22A. It should be further appreciated that the shelf 518and the magazine 270 cooperate such that the cartridge 224 is orientedin the library 202 such that the faces of the cartridge 224 with thegreatest surface areas (in this particular case, faces 226A, 226B of theLTO data cartridge 224) each lie in a vertical plane. Moreover, eachpair of cleats substantially ensures that the cartridges 224 containedin any magazines 270 are oriented such that the faces 226A, 226B of thecartridge 224 with the greatest surface areas each lie in a verticalplane that is substantially perpendicular to the axis or direction inwhich the cleats 522B, 522C allow the magazine 270 to be displaced,namely, along the y-axis. Orienting the cartridges 224 in this mannercontributes to a high data density footprint.

With continuing reference to FIG. 22C, it should also be appreciatedthat cleats 522B and 522C each serve as a guide for a magazine 270 thatmay be disposed on the planar member 520 adjacent to the magazine 270.To elaborate, the upper guide 526A of cleat 522B serves to capture therail 292A of the magazine 270 and the lower guide 526B of the cleat 522Bwill serve to capture the rail 292B of any magazine 270 that is disposedon the planar member 520 immediately adjacent to one side of themagazine 270. Likewise, the lower guide 526B of the cleat 522C serves tocapture the rail 292B of the magazine 270 and the upper guide 526A ofthe cleat 522C will serve to capture the rail 292A of any magazine 270that is disposed on the planar member 520 immediately adjacent to theother side of the magazine 270.

With reference to FIGS. 7A-7B and 8A-8B, each shelf of the shelf system208 that has an immediately overlying shelf is vertically spaced fromthe immediately overlying shelf by a distance that is only slightlygreater than the distance between the bottom side 278 of the magazine270 and the surface associated with a cartridge 224 that is properlylocated in the magazine 270 and furthest from the bottom side 278 of themagazine 270. This spacing between shelves also contributes to achievinga high data density footprint.

It should also be appreciated that the shelf system 208 is capable ofbeing modified in a number of ways. The following sets forth, withoutlimitation, some possible modifications or alternative embodiments. Forexample, a shelf system embodiment is feasible in which each shelf iscapable of supporting only a single magazine 270. An alternativeembodiment is a shelf system that employs a structure other than aplanar member to support one or more magazines 270. For instance, ashelf that utilizes two, L-shaped brackets to support a magazine 270 isfeasible. Further, in yet another alternative embodiment, a shelf systemin which a shelf provides support to a magazine 270 other than from alocation below the magazine 270 is also practicable. Depending upon thedesign of a magazine 270, a shelf that provides support to: (a) one sideof the magazine 270; (b) both of sides of a magazine 270; or (c) the topsurface of a magazine 270 is feasible. An embodiment of a shelf that istilted to prevent undesired displacements of a magazine 270 is alsopracticable. Such a shelf would avoid the need for a latch structure,such as receptacle 530. Further, a shelf embodiment that incorporates anactive latch or retention structure that is actuated by a magazinetransport embodiment is also possible. A shelf system in which there isgreater vertical spacing between shelves is practicable but in mostcases will compromise the data density footprint of the library 202.Further, the shelf system 208 holds magazines 270 in a grid array or X-Yarray. A shelf system 208 embodiment that holds magazines 270 indifferent arrays is also feasible. Another embodiment of a shelf systemcomprises one or more fixed slots each for holding a cartridge 224.Among the types of cartridges that can be held in such a fixed slot is a“cleaning” cartridge, i.e., a cartridge that is adapted to clean readingand writing heads associated with a drive 180.

As shown in FIG. 8B, each of the drives 180 has a horizontal orientationwith the long dimension of the receptacle for receiving a cartridge 224extending horizontally. It should be appreciated that it is feasible foreach of the drives 180 to have a different orientation, such as verticalorientation. It is also possible to have one or more drives 180 with oneorientation and one or more drives 180 with a different orientation. Itshould also be appreciated that the orientation or orientations of thedrives 180, the orientation or orientations of cartridges 224 stored inthe library 202, and the orientations of the drives 180 relative to thecartridges 224 generally dictate the manner in which the cartridgetransport 212 must manipulate the cartridges 224.

Typically, all of the drives 180 are one of an LTO, SAIT and DLT tapedrive. The library 202 is capable of being adapted to accommodate othertape drives. Moreover, the library 202 is adaptable to drives thatoperate on other types of cartridges, such as disk cartridges,cartridges comprising a disk drive.

With reference to FIG. 8B, the library 202 is capable of accommodatingup to twenty-four, full height drives, where each of the drives is oneof an LTO, SAIT or DLT tape drive. The library 202 is also capable ofaccommodating up to forty-eight, half-height drives, where each of thedrives is one of an LTO, SAIT or DLT tape drive. The library 202 iscapable of being modified to accommodate greater or lesser numbers ofdrives. However, the library 202 must have at least one drive to befunctional. Also feasible are combinations of full-height andhalf-height drives.

As shown in FIG. 24A-F, each of the drives 180 in the library 202 ismounted in a drive bay assembly, such as the drive bay assembly 540,that provides the ability to relatively quickly mount and demount adrive 180 from the library 202. Generally, this ability is achievedusing: (a) a sled, such as 548A used herein as a generic sled elementfor illustrative purposes, that is capable of holding a drive 180; (b) ahousing, such as the drive bay housing 550, for receiving the sled 548A;and (c) a plug structure, such as the plug assembly 588, that allows adrive 180 that has been attached to a sled 548A to be mounted byinserting the sled 548A into the housing and demounted by removing thesled 548A from the housing.

With reference to FIGS. 23A-23C, an embodiment of a drive bay assembly540 is described. The drive bay assembly 540 is capable of accommodatingup to four, full-height drives or up to eight, half-height drives, andvarious combinations of full-height and half-height drives. The drivebay assembly 540 is mounted to a ladder frame 542 that defines sixcompartments 544A-544F that are each capable of accommodating one of thedrive bay assembly 540. Generally, when the drive bay assembly 540 ismounted in one of the compartments 544A, 544B, 544C, 544D, 544E and 544Fand a drive 180 is mounted in the drive bay assembly 540, the receptacle186 of the drive 180 is positioned so that the cartridge transport 214can insert a cartridge 224 into and extract a cartridge 224 from thedrive 180. The sled 548A holding the drive 180 is accessible to anoperator by opening the hinged door 348. Consequently, the operator isable to remove the sled, or drive bay assembly 540 comprising the foursleds 548A-D in one embodiment, and associated drive 180 from thelibrary 202 without substantial exposure to the magazine transport 212or cartridge transport 214. Similarly, the operator is also able toinsert a sled, or drive bay assembly 540 comprising the four sleds548A-D in one embodiment, and a drive 180 into the library 202 withouthaving any substantial exposure to the magazine transport 212 or thecartridge transport 214. FIG. 23A illustrates the drive bay assembly 540populated with four drives 546A, 546B, 546C and 546D that, if the drivebay assembly 540 were mounted to the ladder frame 542, would bepositioned for insertion and extraction of cartridges 224 by thecartridge transport 214. Similarly, FIG. 23B illustrates the drive bayassembly 540, with the assembly's four sleds 548A, 548B, 548C and 548Dthat, if the drive bay assembly 540 were mounted to the ladder frame542, would be positioned for extraction and insertion operations by anoperator.

With reference to FIGS. 24A-24F, the drive bay assembly 540 is comprisedof a housing 550 that defines four drive bays 552A, 552B, 552C and 552Dthat are each capable of accommodating a single drive 180. The housing550 also defines a quad unit interface processor bay 554 for holding aQuad unit Interface Processor (“QIP”) 668 that is used to receive power,control and data signals and distribute the signals to any drivesresiding in the housing 550. The housing 550 further includes a firstmounting flange 556 with a first pair of notches 558A, 558B and a secondmounting flange 560 with a second pair of notches 562A, 562B. The firstpair of notches 558A, 558B and second pair of notches 562A, 562Brespectively corresponds with a first pair of threaded holes 564A, 564Band a second pair of threaded holes 566A, 566B associated with eachcompartment of the ladder frame 542. To mount the drive bay assembly 540to the ladder frame 542, the notches 558A, 558B of the mounting flange556 and the notches 562A, 562B of the mounting flange 560 arerespectively aligned with the threaded holes 564A, 564B, 566A and 566Bof the ladder frame 542 and then bolts or screws are used to secure thedrive bay assembly 540 to the ladder frame 542. Demounting of the drivebay assembly 540 from the ladder frame 542 is accomplished by removingthe bolts or screws.

The drive bays 552A-552D are substantially identical to one another.Consequently, only drive bay 552B is described with the understandingthat the description is also applicable to the other drive bays. Drivebay 552B is comprised of a top wall 570A, a bottom wall 570B, a firstside wall 570C, and a second side wall 570D that define an interiorspace 572 for accommodating a sled 548B, a first open side 574A, and asecond open side 574B. When the drive bay assembly 540 is mounted in thelibrary 202, the first open side 574A is adjacent to the space withinwhich the cartridge transport 214 operates and the second open side 574Bis adjacent to the hinged door panel 348. Associated with the first openside 574A are a pair of alignment pins 576A, 576B that cooperate with apair of alignment holes (not shown) associated with the sled 548B toalign the sled 548B in the bay 552B. Associated with the bottom wall570B is a sled guide 578. The sled guide 578 comprises a base member 580and two side members 582A, 582B that cooperatively form a guide for asled 548B. The base member 580 also defines a plug notch 584 thataccommodates a plug, such as the plug assembly 588, that is alsoassociated with the bottom wall 570B. The base member 580 is supportedabove the bottom wall 570B to form a space for accommodating theconductors, such as the plugs 590A and 590B, that provide power, controland data signals to a drive associated with a sled 548B. A spring-loadedflag 586 is attached to the base member 580. In operation, the springassociated with the flag 586 causes the flag 586 to be oriented as shownin FIG. 24C when no sled 548B is associated with the drive bay 552B. Inthis orientation, the flag 586 prevents or inhibits an operator fromreaching through the drive bay 552B and into the space where themagazine transport 212 and/or cartridge transport 214 could possiblyinjure the operator. When a sled 548B is inserted into the drive bay552B, the insertion of the sled causes the flag 586 to rotate towardsthe base member 580. Also associated with the bottom wall 570B is a plugassembly 588 that comprises a first female plug 590A for receiving oneor more power-related signals for a drive 180, a second female plug 590Bfor receiving control and/or data signals for a drive 180, and amulti-conductor ribbon cable 592 for conveying the power-related signalsand the control and/or data signals to and from the QIP 668.

The QIP bay 554 has a front side wall 594A, top side wall 594B, bottomside wall 594C, first side wall 594D, and second side wall 594E. Thefront side wall 594A accommodates a plug interface (not shown) thatmates with a plug interface associated with the QIP 668 and with one ormore plugs (not shown) that is/are connected to the ribbon cablesassociated with the plug assemblies of each of the drive bays 552A-552D.The second side wall 594E and the first side walls associated with thedrive bays 552A, 552C respectively define gaps for the ribbon cables 592associated with the plug assemblies 588 of each of the drive bays552A-552D. The gap 596A receives the ribbon cables 592 associated withthe plug assemblies 588 of drive bays 552A, 552B. The gap 596B receivesthe ribbon cables 592 associated with the plug assemblies 588 of drivebays 552C, 552D. The ribbon cable 592 associated with the drive bay 552Bextends through a passageway 598A and under the base member 570B of thesled guide 578 associated with drive bay 552A to reach the gap 596A.Similarly, the ribbon cable 592 associated with the drive bay 552Dextends through the passageway 598B and under the base member 570B ofthe sled guide 578 associated with drive bay 552C to reach the gap 596B.

The drive bay assembly 540 further comprises the four sleds 548A, 548B,548C and 548D, which are substantially identical to one another.Consequently, only sled 548A is described in combination with one drivebay 552A with the understanding that the description is also applicableto sleds 548B-548D and sleds 552B-D. As will be appreciated to oneskilled in the art, one drive sled, such as 548A is capable ofcooperating with any of the drive bays 552A-D. Before describing thesled 548A, the plug interface associated with a typical drive 180 isdescribed. With reference to FIG. 25, the typical drive 180 (see FIGS.5A-5C) comprises a back surface 602 that typically comprises a powerplug 604 for receiving a power signal (typically, +5V and +12V signals)and a control/data plug 606 for receiving control signals and datasignals. In the absence of the drive bay assembly 540, the drive 180would be oriented in the library 202 such that the receptacle 186 wouldbe accessible by the cartridge transport 214. Typically, the drive 180would also be fixed to a frame within the library 202 with screws thatengage a first pair of threaded holes 608A, 608B associated with thethird surface 190B of the drive and a second pair of threaded holes (notshown) associated with the opposite surface of the drive 180. In such asituation, removal of the drive 180 from the library 202 would requirethat: (a) the cable that provides power to the drive 180 be disconnectedfrom the power plug 604, which typically involves unscrewing screws orunlatching latches in addition to manipulating the cabling; (b) thecable that provides control and data signals to the drive 180 bedisconnected from the control/data plug 606, which also typicallyinvolves unscrewing screws or unlatching latches in addition tomanipulating the cabling; and (c) the screws connecting the drive 180 tothe sled 548A be removed.

With the foregoing description of the plug interface of a typical drive180 and the manner in which the drive 180 is typically fixed in place ina library 202 in mind, the sled 548A generally serves to: (a) provide astructure to which a drive 180 can be fixedly mounted; and (b) provide aplug interface for the drive 180 that faces the opposite direction fromplug interface associated with the drive 180. As a consequence, when thesled 548A is used in combination with the drive bay 552A or any otherdrive bay 552B-D of the housing 550, a drive 180 held by the sled 548Acan be removed from the library 202 without having to undo screws orother fasteners, as required by the conventional approach. Further, whenthe sled 548A and an associated drive 180 are removed from the library202, the electrical connections with the drive 180 are severed byremoving the sled 548A from the drive bay 552A. Conversely, a drive 180can be inserted into the library 202 using the sled 548A and the drivebay 552A without having to manipulate screws or fasteners in the mannerrequired by the conventional approach. Further, during such aninsertion, the electrical connections for the drive 180 are establishedby inserting the sled 548A into the drive bay 552A.

With reference to FIGS. 26A-26C, the sled 548A comprises a housing 612that is capable of accommodating a full-height LTO, SAIT or DLT tapedrive or two, half-height LTO, SAIT or DLT tapes drives. The housing 612comprises a top wall 614A, bottom wall 614B, first side wall 614C, andsecond side wall 614D that define an interior space 616 for holding afull-height drive or two, half-height drives and an opening 618 forreceiving the drive or drives into the interior space. Associated withthe first side wall 614C are three pairs of holes 620A, 620B, 622A,622B, 624A and 624B. Similarly, associated with the second side wall614D are three pairs of holes 626A, 626B, 628A, 628B, 630A and 630B.These holes 620A, 620B, 622A, 622B, 624A, 624B, 626A, 626B, 628A, 628B,630A and 630B allow most, if not all, of the presently known LTO, SAITand DLT tape drives, both full-height and half-height, to be mounted inthe housing 612. Also, associated with the second side wall 614D is areference flag 632 for use by the magazine transport 212 and/or thecartridge transport 214 in locating a sled 548A and any drive held bythe sled 548A. Associated with the bottom wall 614B are a pair of rails634A, 634B. The rails 634A, 634B are spaced so as to be received by theguide formed by the base member 580 and two side members 582A, 582B ofthe sled guide 578. The rails 634A, 634B respectively includereceptacles 636A, 636B. The receptacles 636A, 636B respectively receivethe alignment pins 576A, 576B when the sled 548A is properly insertedinto the drive bay 552A. A hole 638 that provides access to a “tapewind” screw of a drive 180 located in the housing 612 is also associatedwith the bottom wall 614B of the housing 612.

The sled 548A further comprises a back wall assembly 640 that adjoinsthe top wall 614A, bottom wall 614B, first side wall 614C, and secondside wall 614D. The back wall assembly 640 comprises a housing 642 thatsupports a plug structure 644 for connecting a drive 180 held by thehousing 612 with the plug assembly 588 associated with any one of thedrive bays 552A-552D. The plug structure 644 comprises: (a) a first pluginterface 646 that is located to engage the plug assembly 588 associatedwith the drive bay 552A when the sled 548A is properly aligned andinserted into the drive bay 552A; (b) a second plug interface 648 forengage the plug interface associated with the back surface 602 of adrive 180; and (c) conductors 650 extending between the first and secondplug interfaces 646, 648. More specifically, the first plug interface646 comprises a first power plug 652A and a first data/control plug 652Bthat are respectively located to engage the power plug 590A anddata/control plug 590B of the plug assembly 588 when the sled 548A isproperly inserted into the drive bay 552A. The second plug interface 648comprises a second power plug 654A and a second data/control plug 654Bfor respectively engaging the power plug 604 and data/control plugs 606associated with the back surface 602 of a drive 180. The conductors 650comprise: (a) power conductors 656A that connect the first power plug652A and the second power plug 654A; and (b) data/control conductors656B that connect the first data/control plug 652B and the seconddata/control plug 654B. For accommodating two, half height drives, thesecond plug interface 648 further comprises an additional data/controlplug 658 and an additional power plug (not shown) that passes throughholes 659 of the housing 642.

Also associated with the housing 642 is a fan 660 that is used to coolany drive 180 located within the housing 612 by causing air to move fromthe interior space 616 of the housing 612 to the exterior of the housing612 via a grill 662. Further associated with the housing 642 is a handle664 that facilitates insertion/removal of the sled 548A into/from thedrive bay 552A.

By way of example, use of the drive bay assembly 540 comprisesmechanically associating a drive 180 with a sled 548 by using screws toattach the drive 180 to the housing 612 and electrically associating thedrive 180 with the sled 548 using the second plug interface 648. Oncethe drive 180 has been mechanically and electrically associated with thesled 548A, the drive 180 can be associated with the library 202 byinserting the sled 548A into one of the drive bays 552A-552D, such as552A for example, and dissociated from the library 202 by removing thesled 548A from the drive bay 552A.

The drive bay assembly 540 further comprises a QIP 668 that is housed inthe QIP bay 554 and operates to distribute power, control signals anddata to each of the drive bays 552A-552D. The QIP 668 comprises a backpanel 670 with a handle 672 that facilitates insertion/extraction of theQIP 668 into/from the QIP bay 554.

It will be appreciated by one skilled in the art that the drive bayassembly 540 suitable is capable of numerous modifications. Thefollowing sets forth, with limitation, some possible modifications. Forinstance, a drive bay assembly 540 is feasible in which the drive bayhousing 550 is not susceptible to being readily mounted and demountedfrom the frame 542 of a library 202. Further, a drive bay assembly 540is feasible that has a different number of drive bays, such as the drivebay 552A. Additionally, a drive bay assembly 540 that is adapted to holdone or more drives 180 in an orientation other than a horizontalorientation is feasible in one embodiment. Further, a drive bay, such asthe drive bay 552A, that accommodates different types of drives, such asdisk drive, is also practicable. In yet another alternative embodiment,a drive bay 540 without a QIP bay 554 and/or QIP 668 is likewisefeasible. Further, it should also be appreciated that a drive bayassembly 540 is not required for a functional magazine-based datacartridge library 202.

Generally, the power supply system 216 provides DC power to the drives180 using a flat conductor 686 that has a substantially rectangularcross-section, rather than a conventional conductor that has circularcross-section. The use of a flat conductor 686 allows the space within alibrary 202 to be more efficiently used or used to accommodate morecartridges 224 and/or more drives 180.

With reference to FIGS. 27A-27D, the power supply system 216 comprises apower supply 217 comprised of a box-like housing structure with a topside 676A, bottom side 676B, front side 676C, back side 676D, first side676E, and second side 676F. Associated with the front side 676C areseven power supply bays 678 each capable of accommodating a sub-powersupply (not shown). Generally, the power supply 217 includes a sub-powersupply in one of the bays 678 for providing DC power to elements in thelibrary 202 other than the drives 180. The six other bays 678 arepopulated with sub-power supplies depending on the number of drive bayassemblies 540 that are attached to the ladder frame 542. Generally, onesub-power supply is required for each drive bay assembly 540 attached tothe ladder frame 542. Also associated with the front side 676C of thepower supply 217 is a pair of AC receptacles 680, with each receptacle680 capable of accommodating an AC plug through which AC power isprovided to the power supply 216 for conversion to DC power. Alsoassociated with the front side 676C, is a set of breakers 682 thatoperate to sever the connection with the source of AC power when thepower supply 216 is in an undesirable operating state, such as when thepower supply 216 is drawing too much current from the AC source. Thefirst side wall comprises a slot for accommodating an embodiment of aflat electrical power conductor 686 that has a first flat exterior face686A and a second flat exterior face 686B that extends substantiallyparallel to the first flat exterior face 686B.

The flat, electrical power conductor 686 extends vertically and adjacentto one side of the ladder frame 542. In the illustrated embodiment, onlyone vertical standard 688 of the ladder frame 542 is shown. The flat,electrical power conductor 686 is supported by a channel member 690,which is attached to the ladder frame 542. The channel member 690, inaddition to supporting the flat, electrical power conductor 686, alsosupports six power plugs 692A, 692B, 692C, 692D, 692F and 692F, one plugfor each of the compartments 544A, 544B, 544C, 554D, 554E and 544F ofthe ladder frame 542. Each compartment 544A-544F of the ladder frame 542is capable of accommodating a drive bay assembly 540 that, in turn, iscapable of accommodating up to four full height drives and up to eighthalf-height drives.

The flat, electrical power conductor 686 is attached to the channelmember 690 using a plurality of hole hangers 694 that are attached tothe conductor 686 and that each fit over a stud 696 extending from thechannel member 690. The electrical connection between the flat,electrical power conductor 686 and each of the plugs 692A-692F isachieved with taps 698A, 698B, 698C and 698D that are each connected toone of the planar electrical conductors comprising the flat, electricalpower conductor 686. To elaborate, any of the drives 180 that can beassociated with a drive bay assembly 540 and the QIP 668 associated witha drive bay assembly 540 presently require a +5V signal, a +12V signal,and two ground paths (one for each of the voltage signals).Consequently, the flat, electrical power conductor 686 is a laminate offour electrical conductors, one for each of the two voltage signals andone for each of the two ground paths. If the library 202 is modified sothat different electrical signals are required, the flat, electricalpower conductor 686 can be modified accordingly.

As shown in FIG. 27E, an electrical power connection is establishedbetween the flat, electrical power conductor 686 and a drive bayassembly 700 in compartment 544F using a plug 702 that is associatedwith the QIP 668 of the drive bay assembly 700 and that mates with theplug 692F. An electrical connection is established between the flat,electrical conductor 686 and the power supply 216 by a tap assembly 704that extends between the conductor 686 and the points in the powersupply 216 that provide the necessary voltage signals and ground paths.It should be appreciated that the tap assembly 704 comprises ahorizontally extending flat power conductor.

The distance between the first and second flat external faces 686A, 686Bof the flat, electrical power conductor 686 is approximately 0.32inches. In contrast, if a conventional round cable or bundled group ofround cables were designed to be able to provide power to the sametwenty-four drives 180, the cable or group of cables would have across-sectional measurement on the order of 3-4 inches.

It should be appreciated that the substantially rectangularcross-section shape of the flat, electrical power conductor 686 iscomplementary to the shapes of most of the other elements in the library202. As a consequence, the flat, electrical power conductor 686facilitates the layout of the library 202. In this regard, the flatsurfaces 686A, 686B are located so as extend substantially parallel orperpendicular to many of the surfaces associated with elements residingin the library 202. For instance, the flat surfaces 686A, 686B extendsubstantially parallel or perpendicular to the exterior surfaces of thehousing 550 of the drive bay assembly 700. A horizontally extendingflat, electrical power conductor, should one be needed, is also likelyto facilitate the layout of a library 202.

It will be appreciated by one skilled in the art that the flat,electrical power conductor 686 provides benefits in addition to spatialand/or layout related benefits. Namely, the power conductor 686 has alarge capacitance that allows power to be provided to the drives in ahighly responsive manner. Further, “noise” generated by the electricalpower conductor 686 is lower than conventional means. In addition,relative to the conventional round conductors, the flat electrical powerconductor 686 utilizes fewer connectors and/or plugs resulting inadditional noise reduction. It will be further appreciated to oneskilled in the art that a flat, electrical power conductor 686 can alsobe applied to a cartridge-based library.

With reference to FIGS. 7B and 23C, the user definable space 336 is aspace in which the operator of the library 202 has a choice as to theidentity of the functional element or elements of the library 202 thatoccupies all or a portion of the space.

The extent of the user definable space 336 of the library 202 is largelydefined by the ladder frame 542. To elaborate, the user definable space336: (a) extends vertically from approximately the top side 676A of thepower supply 216 (which is located immediately under the lower-mostcompartment of the ladder frame 542, namely, compartment 544A) to thebottom side of cross-member 708; and (b) extends laterally between firstand second sides 710A, 710B of the ladder frame 542. With reference toFIG. 16, the depth of the user definable space 336 extends from plane330B to a substantially parallel plane located adjacent to the backsurface 340B of the library 202. Further, the ladder frame 542substantially divides the user-definable space 336 into six, equallysized spaces, namely, the compartments 544A-544F.

As previously noted, each of the compartments 544A-544F is capable ofaccommodating one of the drive bay assembly 540. Moreover, the ladderframe 542 and the first and second mounting flanges 556, 560 facilitatethe mounting and demounting of the drive bay assembly 540 from any oneof the compartments 544A-544F. To reiterate, mounting of the drive bayassembly 540 in one of the compartments 544A-544F is accomplished byaligning: (a) the first pair of notches 558A, 558B associated with thefirst mounting flange 556 of the drive bay assembly 540 and the firstpair of threaded holes 556A, 556B associated with a selected one of thecompartments 544A-544F; and (b) the second pair of notches 562A, 562Bassociated with the second mounting flange 560 of the drive bay assembly540 and the second pair of threaded holes 566A, 566B associated with theselected one of the compartments 544A-544F. Once the notches arealigned, bolts or screws are then used to secure the drive bay assembly540 to the ladder frame 542. Demounting of the drive bay assembly 540from the ladder frame 542 is accomplished by first removing the bolts orscrews, and then removing the drive bay assembly 540 from the ladderframe 542.

With reference to FIGS. 28A-28B, each of the compartments 544A-544F isalso capable of accommodating a magazine bay assembly 714 that providestwo shelves, namely first and second shelves 730 and 734, that are eachcapable of accommodating two magazines 270. The magazine bay assembly714 comprises a housing with a top wall 716A, a bottom wall 716B, afirst side wall 716C, a second side wall 716D, and a back wall 716E thatdefine an interior space 718 for holding up to four magazines 270. Thetop wall 716A, bottom wall 716B, first side wall 716C and second sidewall 716D also define an opening 720 through which any magazines 270 canbe inserted into and removed from the interior space 718.

The magazine bay assembly 714 further comprises a first mounting flange722 with a first pair of notches 724A, 724B, and a second mountingflange 726 with a second pair of notches 728A, 728B. Mounting of themagazine bay assembly 714 to the ladder frame 542 and demounting themagazine bay assembly 714 from the ladder frame 542 are done insubstantially the same manner as the drive bay assembly 540 is mountedand demounted from the ladder frame 542. Consequently, the mounting anddemounting of the magazine bay assembly 714 is not described further.

The magazine bay assembly 714 further comprises a first shelf 730capable of accommodating up to two magazines 270. The first shelf 730 isformed from the bottom wall 716B and three cleats 732A, 732B and 732Cthat are each substantially identical to the previously described cleat522A. The magazine bay assembly 714 further comprises a second shelf 734that is also capable of accommodating up to two magazines 270. Thesecond shelf 734 is formed from: (a) a planar member 736 that extendsbetween and is attached to the first and second side walls 716C, 716D;and (b) three cleats 738A, 738B and 738C, that are each substantiallyidentical to the previously described cleat 522A. The operation of eachof the first and second shelves 730, 734 is substantially identical tothe operation of the previously described shelf 518. Consequently, theoperation of the shelves 730, 734 is not described. It should, however,be noted that located between the back wall 716E and the cleats732A-732C is a bias element 740 that applies a force to the cleats732A-732C that prevents the cleats 732A-732C from coming out of theholes (not shown) that receive the cleats 732A-732C in the bottom wall716B. A bias element 742 performs the same function with respect tocleats 738A-738C. Such bias elements 742 are also present in the fixedshelving of the shelf system 208 in the library 202 and perform the samebias function.

Based on the foregoing, a user or operator is able to choose whether adrive bay assembly 540 or a magazine bay assembly 714 resides in each ofthe compartments 544A-544F associated with the user-definable space 336.Moreover, altering a choice is, due to the mounting structures employed,relatively easy. It will be appreciated by one skilled in the art that:(a) the user-definable space 336 is a fixed space; (b) the compartments554A-F each have a fixed size, a fixed location and substantially thesame size as the other compartments; and (c) the drive bay assembly 540and the magazine bay assembly 714 are also of substantially of the samesize. A number of modifications to the user-definable space 336 oralternative embodiments are feasible. Among the possible modificationsor alternative embodiments are, without limitation, a user definablespace that has an alterable size; compartments of varying number,location, and/or size; and/or assemblies for placing in the space thatare of different sizes are feasible. Further, other mounting structuresare feasible. For example, a ladder frame 542 or similar structure witha mounting structure that provides a high degree of flexibility as tothe location that a module is mounted is feasible.

Generally, the magazine transport 212 is comprised of: (a) a magazinepicker 880 that operates to move a magazine 270 to and from a magazinestorage location, such as a shelf from the shelf system 208 in thelibrary 202; and (b) an elevator 750 that operates to move the magazinepicker 880 adjacent to the locations in the library 202 at whichmagazines 270 can be stored. It will be appreciated by one skilled inthe art that the locations in a magazine-based library 202 at whichmagazines 270 can be stored include: (a) a fixed shelf or shelves 208;(b) an entry/exit port 206; and (c) a pass-through port, such as themagazine pass-through port 1358 from FIG. 45A. Further, in certainembodiments, the elevator 750 also positions the magazine picker 880adjacent to the drive 180 or drives in the library 202.

With reference to FIGS. 29A-29H, the magazine transport 212 comprises anelevator 750 for moving a magazine picker 880 along horizontal andvertical axes so that the magazine picker 880 can be positioned adjacentto the entry/exit port 206, any shelf of the shelf system 208, and anyof the drives 180. In this regard, the elevator 750 comprises: (a) avertical axis assembly 752 for moving a magazine picker 880 verticallywithin the library 202, and (b) a horizontal axis assembly 754 formoving the magazine picker 880 horizontally within the library 202. Thevertical axis assembly 752 supports or carries the magazine picker 880and generally extends from a first end 756A to a second end 756B.

Generally, the horizontal axis assembly 754 supports the first andsecond ends 756A, 756B of the vertical axis assembly 752 and is capableof applying a horizontal driving force to each of the first and secondends 756A, 756B to horizontally displace the vertical axis assembly 752within the library 202. In this regard, the horizontal axis assembly 754comprises: (a) top assembly 758A for supporting and applying ahorizontal force to the first end 756A of the vertical axis assembly752; (b) a bottom assembly 758B for supporting and applying a horizontalforce to the second end 756B of the vertical axis assembly 752; and (c)a coordination assembly 758C for coordinating the application ofhorizontal forces to the first and second ends 756A, 756B of thevertical axis assembly 752 by the top assembly 758A and the bottomassembly 758B.

With reference to FIG. 29B, the top assembly 758A comprises a U-shapedchannel 760 with a first side, second side 762B and third side 762C. Thefirst side 762A is operatively attached to the interior side of the topsurface 340E of the frame 102. The second side 762B serves as a guidefor a set of rollers 816A, 816B associated with the first end 756A ofthe vertical axis assembly 752. In addition, the second side 762B alsosupports a pair of horizontal stops 764A, 764B that cooperate with astop block 820 that is associated with the first end 756A of thevertical axis assembly 752 to limit the horizontal extent over which thehorizontal axis assembly 754 can move the vertical axis assembly 752.The third side 762C supports a first pulley block 766A and associatedpulley 766B. In addition, the third side supports a second pulley block768A and associated pulleys 768B, 768C. Extending between the pulley766B and the pulley 768B is a belt 770. Associated with the belt 770 isa mount 772 for connecting the belt 700 to the first end 756A of thevertical axis assembly 752. The mount 772 also incorporates a structurethat allows the tension of the belt 770 to be adjusted. The pulley 768Cis associated with another belt 798 that is used to: (a) transmit theforces that are used to horizontally displace the first end 756A of thevertical axis assembly 752 via the belt 770 and mount 772; and (b)coordinate the operation of the top assembly 758A with the bottomassembly 758B.

With reference to FIG. 29C, the bottom assembly 758B comprises aU-shaped channel 776 with a first side 778A, second side 778B and thirdside 778C. The first side 778A is operatively attached to the interiorside of the bottom surface 340F of the frame 102 and supports a guideshaft 780 that receives a linear bearing 822 associated with the secondend 756B of the vertical axis assembly 752. The guide shaft 780 issupported by a set of stand-offs 782 that are operatively connected tothe first side 778A. The guide shaft 780 also comprises a pair of guidestops 784A, 784B that limit the horizontal extent over which thehorizontal axis assembly 754 can move the vertical axis assembly 752.The first side 778A also supports a home position sensor 786 thatdetects when the vertical axis assembly 752 is positioned adjacent tothe end of the guide shaft 780. The third side 778C supports a firstpulley block 788A and associated pulley 788B. In addition, the thirdside 778C supports a second pulley block 790A and associated pulleys790B, 790C. Extending between the pulley 788B and the pulley 790B is abelt 792. Associated with the belt 792 is a mount 794 for connecting thebelt 792 to the second end 756B of the vertical axis assembly 752. Themount 794 also incorporates a structure that allows the tension of thebelt 792 to be adjusted. The pulley 790C is associated with another belt798 that is used to: (a) transmit the forces that are used tohorizontally displace the first end 756A of the vertical axis assembly752 via the belt 770 and mount 772; and (b) coordinate the operation ofthe top assembly 758A with the bottom assembly 758B.

With reference to FIGS. 29A-29C, the coordinating assembly 758Ccomprises the pulley 768C associated with the top assembly 758A, thepulley 790C associated with the bottom assembly 758, and a belt 798 thatextends between the pulley 768C and the pulley 790C. As can beappreciated, the coordinating assembly 758C interfaces with the topassembly 758A and the bottom assembly 758B so that movements of themount 772 associated with the top assembly 758A and the mount 794associated with the bottom assembly 758C are mirrored. As a consequence,when the first and second ends 756A, 756B of the vertical axis assembly752 are respectively attached to the mounts 772, 790 and a motive forceis applied to the mounts 772, 790, the first and second ends 756A, 756Bare displaced in the same manner. It should also be noted that the belt798 is enclosed within a housing 800.

Also associated with the bottom assembly 758B are a DC electrical motor802 and associated motor controller 804 that are used to provide themotive force for horizontally displacing the vertical axis assembly 752.To elaborate, any rotational force produced by the electrical motor 802is transmitted by a motor drive pulley system 806 comprised of a pulley(not shown) that is connected to the electrical motor 802, a drivepulley 808, and a belt 810 extending between the pulleys 808 and (notshown). The drive pulley 808 resides on the same axle (not shown) thatthe pulley 790C and 790B reside. Consequently, rotation of the drivepulley 808 produces a corresponding rotation of the pulleys 790B, 790C.Rotation of the pulley 790B causes the mount 794 to be horizontallydisplaced. Similarly, rotation of the pulley 790C ultimately causes themount 772 to be horizontally displaced in a manner that mirrors thehorizontal displacement of the mount 794. The home position sensor 786is used in conjunction with an encoder associated with the electricalmotor 802 or other position sensor known in the art to determine thehorizontal location of the vertical axis assembly 752.

With reference to FIGS. 29D-29H in conjunction with FIGS. 30A-30G, thevertical axis assembly 752 generally comprises: (a) structures thatinterface the vertical axis assembly 752 with the top and bottomassemblies 758A, 758B; (b) a rail structure that supports a carriage 882that holds the magazine picker 880 and defines the vertical extentthrough which the carriage 882 and associated magazine picker 880 can bedisplaced; and (c) an actuation system that provides the motive forcefor vertically displacing the carriage 880 along the rail structure.

With the foregoing general description in mind, the vertical axisassembly 752 comprises a first pair of guide roller bearings 816A, 816Band a second pair of guide roller bearing 818A, 818B for interfacing thevertical axis assembly 752 with the top assembly 758A of the horizontalaxis assembly 752. More specifically, the second side 762B of theU-shaped channel 760 associated with the top assembly 758A is receivedbetween the first pair of guide roller bearing 816A, 816B and betweenthe second pair of guide roller bearings 816A, 816B to interface thevertical axis assembly 752 with the top assembly 758A of the horizontalaxis assembly 752. A stop block 820 located adjacent to the rollerbearings cooperates with the horizontal stops 764A, 764B of the topassembly 758A to limit the horizontal displacement of the vertical axisassembly 752. The vertical axis assembly 752 further comprises a linearbearing assembly 822 that receives the guide shaft 780 to interface thevertical axis assembly 752 to the bottom assembly 758B of the horizontalaxis assembly 752.

The vertical axis assembly 752 further comprises a rail mount 824 thatholds a linear rail 826 that can be displaced along the length of therail mount 824. An upper rail stop 828 defines the upper limit along therail mount 824 that the linear rail 826 can be displaced. The linearbearing assembly 822 defines the lower limit along the rail mount 824that the linear rail 826 can be displaced. Associated with the linearrail 826 is a pair of carriage blocks 830A, 830B that provide aninterface for a carriage bracket 854 that connects the linear rail 826to the actuation system and to the carriage 882 that supports themagazine picker 880.

The vertical axis assembly 752 further comprises a pulley system 832 isused to vertically displace the linear rail 826 along the rail mount826. The system 832 comprises a housing 834 that supports an upperpulley 836 and a lower pulley 838. Extending between the upper pulley836 and the lower pulley 838 is a belt 840. Associated with the belt 840is a mount 842 for connecting the belt 780 to the carriage bracket 854that is, in turn, connected to the carriage blocks 830A, 830B associatedwith the linear rail 826. The mount 842 also comprises a structure fortensioning the belt 780.

The vertical axis assembly 752 further comprises a DC electric motor 844and motor controller 846 for providing the motive force for moving thelinear rail 826 along the rail mount 826. To elaborate, any rotationforce produced by the DC electric motor 844 is transmitted to the lowerpulley 838 of the pulley system 832 by another pulley system comprisedof a motor pulley 848, a drive pulley 850 that is attached to the sameaxle as the lower pulley 838, and a belt 852 that extends between themotor pulley 848 and the drive pulley 850. Rotation of the lower pulley838, in turn, causes the linear rail 826 to be displaced along the railmount 826.

With reference to FIGS. 29G-29H, the vertical axis assembly 752 furthercomprises a carriage bracket 854 that is used to: (a) mechanicallyconnect the linear rail 826 and the belt 840; and (b) mechanicallyconnects the linear-rail 826 to a carriage 882 that supports themagazine picker 880. To elaborate, the carriage bracket 854 is connectedto the linear rail 826 by screws (not shown) that pass through holes inthe carriage bracket 854 and engage threaded holes in the carriageblocks 830A, 830B, which are fixedly attached to the linear rail 826.The carriage bracket 854 is connected to the belt 840 by: (a) a firstpair of pins 856 that are associated with the mount 842 and pass througha pair of holes associated with the bracket 854; and (b) a second pairof pins 858 that are associated with the mount 842 and pass through asingle slot 860 associated with the bracket 854. The slot 860 allows thesecond pair of pins 858 to move when the tensioning device associatedwith the mount 842 is actuated and still maintain a connection with thebracket 854.

The vertical axis assembly 752 also comprises a channel guide 860 thatholds a flex cable that is used to transmit signals between the controlsystem 218 and magazine picker 880 (as well as any other elementsassociated with the magazine picker 880) as the magazine picker 880 isvertically displaced.

Further comprising the vertical axis assembly 752 is a flag 864 thatinteracts with the home position sensor 786 to indicate when thevertical axis assembly 752 is located adjacent to the end of the guideshaft 780. To elaborate, the flag 864 interrupts an optical signaloutput by the home position sensor 786 to indicate when the verticalaxis assembly is located adjacent to the end of the guide shaft 780.Other sensing schemes are feasible.

The vertical axis assembly 752 further comprises a brake mechanism 868that operates to engage the belt 840 during a loss of power and therebyprevent the magazine picker 880 from dropping to the bottom of thelibrary 202 and potentially being damaged or damaging other componentsof the library 202. The brake mechanism 868 comprises a roller 870 and asolenoid actuated brake assembly 872 that includes a brake shoe 874. Thebrake mechanism 868 operates so that when power is removed from thelibrary 202, the solenoid actuated brake assembly 872 causes the brakeshoe 874 to move so that the belt 840 is pinched between the brake shoe874 and the roller 870, thereby preventing further movement of the belt840. Conversely, when power is being applied to the library 202, thesolenoid actuated brake mechanism 872 operates to hold the brake shoe874 away from the belt 840 so that the belt 840 can be moved as neededfor the operation of the library 202.

The vertical location of the carriage 882 or related elements isprovided using an encoder associated with the DC motor 844 or otherposition sensors known in the art.

It should be appreciated that the elevating function within the library202 and other magazine-based data cartridge libraries can beaccomplished with a number of different elevator designs. For example, acounter-weight elevator is feasible.

With reference to FIGS. 30A-30G, the magazine transport 212 comprises amagazine picker 880 for moving a magazine 270 towards and away from amagazine storage location, such as a shelf in the shelf system 208, oncethe picker 880 has been positioned adjacent to the storage location bythe elevator 750. Generally, the magazine picker 880 comprises: (a) amagazine support 884 for supporting a magazine 270 during movement ofthe magazine 270 towards and away from a storage location in the library202; and (b) a magazine transport device 212 for moving a magazine 270between the magazine support 884 and a storage location in the library202.

Before describing the magazine picker 880, the structure for attachingthe magazine picker 880 to the vertical axis assembly 752 is described.With reference to FIG. 30A, the magazine picker 880 is operativelyconnected to a carriage 882 that is, in turn, connected to the carriagebracket 854 associated with the vertical axis assembly 752.

The magazine picker 880 comprises a support structure 884 for supportinga magazine 270 during transport of the magazine 270 towards and awayfrom a storage location in the library 202. The support structure 884comprises: (a) a base plate 886; (b) four brackets 888A, 888B, 888C and888D mounted to the base plate 886; (c) a pair of rail mounting plates890A, 890B, with the rail mounting plate 890A supported by the brackets888A, 888B and the rail mounting plate 890B supported by the brackets888C, 888D; (d) a pair of rails 892A, 892B, with the rail 892A beingattached to the rail mounting bracket 890A, and the rail 892B attachedto the rail mounting bracket 890B. Each of the rails 892A, 892Bcomprises two grooves 894A, 894B, one for accommodating rail 292A of amagazine 270 and one for accommodating rail 292B of a magazine 270. Inlibrary 202, the shelf system 208 is configured so that all of themagazines 270 stored in the library 202 have the same orientation.Consequently, only one of the grooves 894A, 894B associated with each ofthe 892A, 892B is utilized. For example, groove 894A of rail 892A may beused to accommodate rail 292A of a magazine 270, and groove 894B of therail 892A would not be utilized. Continuing with the example, groove894B of rail 892B would accommodate rail 292B of a magazine 270, andgroove 894A of the rail 892B would not be utilized. The rail mountingplates 890A, 890B and the rails 892A, 892B form a guide during movementsof a magazine 270 to and from a storage location and a support for amagazine 270 during transport of a magazine 270 and during movements ofa magazine 270 to and from a storage location. Receptacles 896A, 896Bare respectively associated with the rail mounting plates 890A, 890B andengage the detents 296A, 296B located on the bottom side 278 of amagazine 270 to inhibit undesired movement of a magazine 270, especiallyduring transportation of a magazine 270 from one storage location toanother storage location.

The magazine transport 212 comprises a magazine transport device 900 formoving a magazine 270 between the support formed by the rail mountingplates 890A, 890B and the rails 892A, 892B and a storage location in thelibrary 202. The magazine transport device 900 comprises: (a) a magazineengagement device 902 that is capable of selectively engaging a magazine270 and disengaging from a magazine 270; and (b) a displacement device904 for moving the magazine engagement device 902.

The displacement device 904 comprises: (a) a linear rail 906; (b) abearing block 908 that is mounted to the linear rail 906, capable ofmoving along the linear rail 906, and supports the magazine engagementdevice 902; (c) a lead screw 910 that is supported by bearings 911A,911B associated with the brackets 888C, 888D; (d) a lead screw nut 912for applying a motive force to the magazine engagement device 902 tomove the device 902 to a desired location along the linear rail 906; (e)a DC motor 914 that is supported by the bracket 888C and provides therotational motive force that causes the lead screw nut 912 to move alongthe lead screw 910; (f) a first gear 916 and a second gear 918 that areused to transfer the rotational force produced by the DC motor 914 tothe lead screw 910; and (g) a center position flag 920 that cooperateswith a detector that is associated with the magazine engagement device902 to indicate when the displacement device 904 has positioned themagazine engagement device 902 over the center of the linear rail 906.

As can be appreciated, when the magazine engagement device 902 isattached to the bearing block 908 and the lead screw nut 912 engages themagazine engagement device 902, the production of a rotational force bythe DC motor 914 causes the lead screw nut 912 to move along the leadscrew 910 and, as a consequence, the magazine engagement device 902 tomove along the linear rail 906. The location of the magazine engagementdevice 902 is determined using an encoder associated with the motor 914or other position sensing device known in the art.

Generally, the magazine engagement device 902 operates so as to “hook” amagazine 270 by rotating a toggle plate 928 with pins 938A, 938B thatare located so as to pass through one of the pair of engagement holes298A, 298B associated with a magazine 270. Disengagement or “un-hooking”of the magazine 270 is accomplished by counter-rotating the toggle plate928.

With the foregoing general description in mind, the magazine engagementdevice 902 comprises a toggle base 924 that is mounted to the bearingblock 908 and a drive block 926 with a hole 927 for receiving a post 925associated with the lead screw nut 912. The magazine engagement device902 further comprises: (a) a toggle plate 928 that is pivotally mountedto the toggle base 924 with a toggle axle 930; and (b) a toggle actuatorsystem 932 for rotating the toggle plate 928 so as to engage a magazine270 and disengage from a magazine 270. The toggle plate 928 has a firstend 934 and a second end 936 with the axis of rotation for the toggleplate 928 located between the first and second ends 934, 936. Associatedwith the first end 934 is a first pair of engagement pins 938A, 938B forpassing through a pair of engagement holes 298A, 298B associated with amagazine 270. Likewise, a second pair of engagement pins 940A, 940B areassociated with the second end 936 and also serve to engage a magazine270 via a pair of engagement holes 298A, 298B associated with themagazine 270. Also associated with the first end 934 is a first sensorassembly 942 that operates to detect the engagement flag structure 300associated with a pair of engagement holes 298A, 298B. To elaborate,when the engagement pins 938A, 938B pass through the engagement holes298A, 298B of a magazine 270 (i.e., when a magazine 270 has been“hooked”), the sensor 942 detects the engagement flag structure 300,thereby confirming that the magazine 270 has been captured. A secondsensor assembly 944 is associated with the second end 936 of the toggleplate 928 and operates in substantially the same manner as the firstsensor assembly 942. In an alternative embodiment, an optical sensorsystem is used to detect the presence or absence of the exterior of thebottom side 278 of the magazine 270 to determine whether or not amagazine 270 has been engaged. The optical sensor system comprises abeam producing element and a reflected beam detecting element. If themagazine 270 has been engaged, the beam produced by the beam producingelement is reflected by the exterior of the bottom side 278 of themagazine 270 and detected by the detecting element. If the magazine 270has not been engaged, the beam produced by the beam producing element isnot detected by the detecting element. One optical sensing system isassociated with each of the first end 934 and second end 936 of thetoggle plate 928. Also associated with the toggle plate 928 is arotational position flag 946 that is used with a detector to indicatethe rotational position of the toggle plate 928.

The toggle actuator system 932 comprises: (a) a stepper motor 950 thatis attached to the toggle base 924; (b) a pinion 952 that is attached tothe spindle of the motor 950; (c) a cluster gear 954 that is attached toattached to the toggle base 924 and has a first gear 956 that engagesthe pinion 952 and a second gear 958; (d) a driven gear 960 that engagesthe second gear 958; (e) an overdrive arm 962; (f) a first springassembly 964 for connecting the driven gear 960 and the overdrive arm962; and (g) a second spring assembly 966 for connecting the overdrivearm 962 and the toggle plate 928. In normal operation, the stepper motor950 produces a rotation force for rotating one of the first and secondends 934, 936 into position to engage a magazine 270. The rotation forceis transmitted to the toggle plate 928 by the pinion 952, cluster gear954, driven gear 960, first spring assembly 964, overdrive arm 962 andthe second spring assembly 964. If, however, the rotation of the toggleplate 928 is inhibited such that the toggle plate 928 cannot reach thedesired rotational position, one of the spring assemblies 964 or 966comes into play to allow the toggle plate 928 to cease rotating beforethe desired rotational position is reached. By allowing the toggle plate928 to cease rotating damage to the motor 950 and engagement pins 940A,940B is avoided, as well as damage to whatever is inhibiting therotation of the toggle plate 928. For example, if the stepper motor 950is applying a force to produce a clockwise rotation of the toggle plate928, as viewed from the stepper motor side of the engagement device 902,and an obstruction is causing a counter-clockwise force to be applied tothe toggle plate 928, the second spring assembly 966 elongates to permitthe toggle plate 928 to cease rotating. When the obstruction is nolonger present, the energy stored in the elongated spring assembly 966causes the toggle plate 928 to rotate to the desired position. The firstspring assembly 964 operates in a similar fashion when an obstructionprevents rotation of the toggle plate 928 in the counter-clockwisedirection.

Also attached to the toggle base 924 is a sensor block 970 thatincludes: (a) a first sensor assembly 972 for cooperating with thecenter position flag 920 to provide an indication as to when therotational axis of the toggle plate 928 is positioned over the center ofthe linear rail 906; and (b) a second sensor assembly 974 forcooperating with the rotational position flag 946 to provide a signalindicative of the rotational position of the toggle plate 928. Theelectrical signals produced at the sensor block 970 are conveyed to aplug 976 by a flex cable 978. The plug 976 extends through the carriage882 and receives a plug (not shown) that is connected to a controllerlocated on the opposite side of the carriage 882 from the magazinepicker 880.

A first detector 982 is attached to bracket 888A and is used to detect,on one side of the magazine picker 880, the end surface 532 of a cleatassociated with a shelf storage location for a magazine 270 and thereference flag 632 associated with a sled, such as sled 548A, in a drivebay assembly 540 located on the one side of the magazine picker 880. Asecond detector 984 is attached to the bracket 888B and serves the samepurpose as the first detector 982 but with respect to any cleats and/orreference flags located on the other side of the magazine picker 880.

With reference to FIGS. 31A-31L, the operation of the magazine picker880 is described with respect to the moving of a magazine 270 from afirst shelf 990 that is associated with the two columns of shelving 528Bto a second shelf 992 that is associated with the five columns ofshelving 528A is described. For clarity, the only elements of themagazine picker 880 that are substantively shown in the noted figuresare the base plate 886, rail mounting plate 890A, rail 892A, and themagazine engagement device 902. Associated with the first shelf 990 is acleat 994 that is functionally equivalent to the cleat 522A that waspreviously discussed. Likewise, a cleat 996 is associated with thesecond shelf 992. The magazine 270 is shown in cross-section so that theinteraction of the magazine engagement device 902 with the engagementholes 298A, 298B of the magazine 270 can be seen.

FIGS. 31A-31B illustrate a preferred idle state for the magazine picker880, namely, with the rotational axis of the toggle plate 928 of themagazine engagement device 902 disposed over the center of the linearrail 906 and the toggle plate 928 in a neutral position. Beforedescribing the movement of the magazine 270, it should be appreciatedthat the elevator 750 has been used to position the magazine picker 880adjacent to the first shelf 990. In this regard, the detector 984 hasbeen used to produce a signal that is used to cause the elevator 750 toposition the magazine picker 880 so that the magazine picker 880 canremove the magazine 270 from the first shelf 990.

With reference to FIG. 31C, movement of the magazine 270 commences withthe magazine displacement device 904 moving the magazine engagementdevice 902 from the idle state location illustrated in FIGS. 31A-31B andin direction 1000A to a location sufficiently adjacent to the magazine270 for the magazine engagement device 902 to engage the magazine 270.Engagement of the magazine 270 by the magazine engagement device 902 isaccomplished by rotating the toggle plate 928 such that the engagementpins 940A, 940B associated with the second end 936 of the toggle plate928 can pass through first engagement holes 1002 (e.g., engagement holes298A, 298B) of the magazine 270 to engage the magazine 270. Theengagement of the magazine 270 is confirmed by the interaction of thesecond sensor assembly 944 with the engagement flag structure (e.g.,engagement flag structure 300) of the magazine 270. Alternatively, theoptical sensor system that detects a signal reflected by the exterior ofthe bottom side 278 of the magazine 270 is used to confirm theengagement.

FIG. 31D illustrates an “over travel” condition that may occur in thecourse of using the magazine engagement device 902 to engage themagazine 270 as shown in FIG. 31C. In an “over travel” situation, themagazine displacement device 904 has moved the magazine engagementdevice 902 in the direction that is opposite to the direction in whichthe magazine 270 is to be moved and has moved the magazine engagementdevice 902 so far in this direction that the magazine engagement device902 cannot engage the magazine 270. In the illustrated case, themagazine displacement device 904 has moved the magazine engagementdevice 902 too far in the direction 1000A for the magazine engagementdevice 902 to engage the magazine 270. As a consequence, when the toggleplate 928 is rotated, the engagement pins 940A, 940B contact the bottomsurface 278 of the magazine 933, rather than pass through the engagementholes 1002. In this situation, the spring assembly 964 allows the toggleplate 928 to cease rotating, thereby preventing potential damage to atleast the stepper motor 950 and the magazine 270.

In one embodiment of the present invention, the “over travel operation”can have the desired effect of the engagement device 902 engaging themagazine 270 in a first attempt. In an over travel operation, themagazine displacement device 904 purposely moves the magazine engagementdevice 902 in a direction 1000A that is opposite to the direction 1001Bin which the magazine 270 is to be moved and moves the magazineengagement device 902 so far in this direction 1000A that the engagementpins 940A, 940B of the magazine engagement device 902 cannot engage themagazine 270 and instead, upon rotation of the toggle plate 928, contactthe bottom surface 278 of the magazine 270. When the engagement pins940A, 940B of the toggle plate 928 contact the bottom surface 278 of themagazine 270, one of the spring assemblies 964A, 964B allows the toggleplate 928 to cease rotating. Subsequently, when the magazinedisplacement device 904 moves the magazine engagement device 902 in thedirection that the magazine 270 is to be moved and the engagement pins940A, 940B reach the engagement holes 1002 of the magazine 270, theenergy stored in one of the spring assemblies 964A, 964B causes thetoggle plate 928 to rotate and the engagement pins 940A, 940B to enterthe engagement holes 1002 of the magazine 270 and thereby positivelyengage the magazine 270 on the first try.

To illustrate the use of the over travel operation, assume the magazine270 is positioned further in the direction 1000B than is illustrate inFIG. 31C. In such a situation, the magazine engagement device 902 maynot be able to engage the magazine 270 if the magazine engagement device902 is operated in a manner that assumes that the engagement holes 1002are in the location illustrated in FIG. 31C. If the magazine 270 is notengaged or cannot be engaged with the magazine engagement device 902 inthis position, the magazine engagement device 902 will have to berepositioned and the engagement operation repeated. Alternatively,should an over travel operation be performed so that the magazineengagement device 902 is positioned further in direction 1000A than isshown in FIG. 31C, the magazine engagement device 902 can then contactthe bottom side 278 of the magazine 270 as shown in FIG. 31D. Once themagazine 270 is contacted in this manner, movement of the magazineengagement device 902 in direction 1000B (which is the direction inwhich the magazine 270 is to be moved anyway) and the operation of thefirst spring assembly 964 will cause the engagement pins 940A, 940B topass through the first engagement holes 1002 of the magazine 270,thereby engaging the magazine 270.

With reference to FIG. 31E, once the magazine 270 has been engaged, themagazine displacement device 904 is used to pull the magazine engagementdevice 902 and the engaged magazine 270 in direction 1000B and onto thesupport formed by the rail mounting plates 890A, 890B and intoengagement with the rails 892A, 892B.

With reference to FIG. 31F, the magazine displacement device 904 isunable to move far enough in the direction 1000B to move the engagedmagazine 270 either completely onto the support structure of themagazine picker 880 or completely off of the first shelf 990.Consequently, the following operations have occurred relative to thestate of the magazine picker 880 shown in FIG. 31E: (a) the toggle plate928 has been rotated in the counter-clockwise direction to disengage thetoggle pins 940A, 940B from the magazine 270; (b) after disengagement,the magazine displacement device 904 has been moved in direction 1000Aso as to position the magazine engagement device 902 to re-engage themagazine (an “over-travel operation” may be employed); and (c) thetoggle plate 928 has been rotated in the clock-wise direction so thatthe engagement pins 938A, 938B associated with the first end 934 of thetoggle plate 928 pass through the engagement holes 1002 to re-engage themagazine 270.

With reference to FIG. 31G, after re-engagement of the magazine 270 bythe magazine engagement device 902, the magazine displacement device 904is used to push the magazine engagement device 902 and the engagedmagazine 270 further in the direction 1000B. At this point, the magazine270 is completely supported by the magazine picker 880 and completelyremoved from the first shelf 990.

At this point, it should be appreciated that: (a) the steps associatedwith moving the magazine 270 from the first shelf 270 to the magazinepicker 880 are exemplary of the steps associated with moving a magazinefrom any shelf in the library or from the entry/exit port to themagazine picker 880; (b) the movement of the magazine 270 from the firstshelf 990 to the magazine picker 880 required two separate displacementsthat were separated from one another by an amount of time associatedwith the disengagement and re-engagement of the magazine; (c) with themagazine 270 fully supported by the magazine picker 880 and completelyremoved from the first shelf 990, the elevator 750 can be used to movethe magazine picker 880 and the magazine 270 to other locations in thelibrary; and (d) the magazine 270 could be moved back onto the firstshelf 990 or any other shelf associated with the two columns of shelving528B.

With reference to FIGS. 31H-31I, the use of the magazine picker to movethe magazine 270 from the magazine picker 880 to the second shelf 992 isdescribed. It should be appreciated that the movement of the magazine270 to any shelf of the shelf system 208 involves similar operations tothose described hereinafter. Relative to the state of the magazinepicker 880 shown in FIG. 31G, the following operations have occurred:(a) the toggle plate 928 has been rotated counter-clockwise to disengagethe magazine engage device 902 from the engagement holes 1002; (b) afterdisengagement, the magazine displacement device 904 has moved themagazine engagement device 902 in the direction 1000A to position themagazine engagement device 902 for engaging the magazine 270; and (c)the toggle plate 928 has been rotated in a counter-clockwise directionso that the engagement pins pass through engagement holes 1004 (e.g.,engagement holes 306A, 306B) and thereby engage the magazine 270. An“under travel operation” may be performed so that it is unlikely thatengagement of the magazine will require more than one attempt. In anunder travel operation, the magazine displacement device 904 purposelymoves the magazine engagement device 902 in a direction that is oppositeto the direction in which the magazine is to be moved and before themagazine engage device 904 is at a location at which the magazine can beengaged, rotates the toggle plate 928 so that the engagement pinscontact the bottom surface 278 of the magazine. When the engagement pinsof the toggle plate 928 contact the bottom surface 278 of the magazine,one of the spring assemblies 964A, 964B allows the toggle plate 928 tocease rotating. Subsequently, when the magazine displacement device 904moves the magazine engagement device 902 further in the direction thatis opposite to the direction in which the magazine is to be moved, theengagement pins reach the engagement holes of the magazine and theenergy stored in one of the spring assemblies 964A, 964B causes thetoggle plate 928 to rotate and the engagement pins to enter theengagement holes of the magazine and thereby positively engage themagazine on the first try.

With reference to FIG. 31J, the magazine displacement device 904 is usedto pull the magazine engagement device 902 and the engaged magazine 270in direction 1000B. At this point, the magazine 270 is supportedpartially by the second shelf 992 and partially by the magazine picker880.

With reference to FIG. 31K, the magazine displacement device 904 isunable to move far enough in the direction 1000B to move the engagedmagazine 270 either completely off of the support structure 884 of themagazine picker 880 or completely on to the second shelf 992.Consequently, the following operations have occurred relative to thestate of the magazine picker 880 shown in FIG. 31J: (a) the toggle plate928 has been rotated in the clockwise direction to disengage the togglepins 940A, 940B from the magazine 270; (b) after disengagement, themagazine displacement device 904 has been moved in direction 1000A so asto position the magazine engagement device 902 to re-engage the magazine270 (an “under-travel operation” may be employed); and (c) the toggleplate 928 has been rotated in the clockwise direction so that theengagement pins 938A, 938B associated with the first end 934 of thetoggle plate 928 pass through the engagement holes 1002 to re-engage themagazine 270.

With reference to FIG. 31L, the magazine displacement device 904 haspushed the magazine engagement device 902 and the engaged magazine 270in direction 10001B so that the magazine 270 is completely supported bythe second shelf 992.

At this point, it should be appreciated that: (a) the steps associatedwith moving the magazine 270 from the magazine picker 880 to the secondshelf 992 are exemplary of the steps associated with moving a magazine270 from the magazine picker 880 to any shelf of the shelf system 208 inthe library 202 or to the entry/exit port 206; and (b) the movement ofthe magazine 270 from the magazine picker 880 to the second shelf 992required two separate displacements that were separated from one anotherby an amount of time associated with the disengagement and re-engagementof the magazine 270.

At this point, the toggle plate 928 can be rotated in acounter-clockwise direction to disengage the magazine 270. After anydisengagement, the magazine 270 displacement device 904 can then be usedto move the magazine engagement device 902 in direction 1000A and returnthe magazine engagement device 902 to the preferred idle position.

The foregoing has described the magazine transport device 212 used inthe library 202. It should, however, be appreciated that other theinvention is not limited to the particular design of the elevator 750.For example, an elevator that operates based on a counter-weightprinciple is also feasible. Further, the invention is not limited to thedesign of the magazine picker 880. For instance, a magazine engagementdevice that operates by grasping oppositely situated surfaces of amagazine 270 between two members, with either one member moving towardsthe other member to grasp the magazine 270 or each member moving towardsthe other member to grasp a magazine 270, is possible. A magazineengagement device that operates by linearly translating one or moreengagement pins to engage a magazine 270 and disengage from a magazine270 is also feasible. For example, FIG. 32 illustrates a magazineengagement device 1008 that uses a linear actuator 1010 to displace acamming device 1012 that, in turn, causes engagement pins 1014A, 1014Bto be linearly translated to engage a magazine 270 and disengage from amagazine 270. Yet another approach is to use a conveyor belt to engageand move a magazine 270 between a support structure 884 and a shelf ofthe shelf system 208.

Generally, the cartridge transport 214 operates to move a data cartridge224 between a magazine 270 and a drive 180. With reference to FIGS.33A-33B, the cartridge transport 214 is comprised of: (a) a cartridgetransport unit 1050; (b) a horizontal transport unit 1052 forhorizontally displacing the cartridge transport unit 1050; and (c) theelevator 750.

With continuing reference to FIGS. 33A-33B, the horizontal transportunit 1052 is attached to a transport chassis 1054 that is, in turn,attached to the vertical axis assembly 752 of the elevator 750. Thetransport chassis 1054, in this embodiment, is an integration of thecarriage 882, the base plate 886, and the brackets 888A-888D, previouslydescribed with respect to the magazine transport 212. It should also benoted that the rail 892A comprises a spring-loaded detent 1055 forengaging one of the notches 295A, 295B associated with a magazine 270 tosecure a magazine 270 on the transport chassis 1054. A secondspring-loaded detent (not shown) is associated with the rail 892B and isused to engage the other of the notches 295A, 295B associated with amagazine 270.

The horizontal transport unit 1052 comprises: (a) a linear rail 1056that is attached to the transport chassis 1054; (b) a rail block 1058that is mounted to the linear rail 1056, capable of moving along thelinear rail 1056, and supports the cartridge transport unit 1050; (c) apair of stop blocks 1060A, 1060B for limiting the range over which therail block 1058 can move along the linear rail 1056; (d) a lead screw1062 that is supported by a pair of brackets 1064A, 1064B that areattached to the transport chassis 1054; (e) a lead screw nut 1066 forapplying a motive force to the cartridge transport unit 1050 to move theunit 1050 to a desired location along the linear rail 1056; (e) a DCmotor 1068 that provides the rotational motive force that causes thelead screw nut 1066 to move along the lead screw 1062, and is supportedby bracket 1070 that is attached to the transport chassis 1054; (f) apinion 1072 that is attached to the spindle of the DC motor 1068; and(g) first gear 1074 and a second gear 1076 that are used to transfer therotational force produced by the DC motor 1068 to the lead screw 1062.

With reference to FIGS. 33C-33D, the cartridge transport unit 1050comprises a carriage block 1080 that is attached to the rail block 1058and engages the lead screw nut 1066. As will be appreciated by oneskilled in the art, upon the application of a rotational motive force bythe DC motor 1068, the lead screw nut 1066 is displaced along the lead1062 and, as a consequence, the cartridge transport unit 1050 ishorizontally displaced along the linear rail 1056. Horizontaldisplacement of the cartridge transport unit 1050 along the linear rail1056 facilitates: (a) positioning of the cartridge transport unit 1050over a particular slot of a magazine 270 supported by the magazinepicker 880 so that a data cartridge 224 can be inserted into the slot ofthe magazine 270 or a data cartridge 224 can be extracted from the slotof the magazine 270; and (b) moving the cartridge transport unit 1050towards and away from a drive 180 during the transfer of a datacartridge 224 between a magazine 270 and the drive 180. The location ofthe cartridge transport unit 1050 is determined using an encoderassociated with the DC motor 1068 or other position sensor known in theart.

With reference to FIGS. 33C-33F, the cartridge transport unit 1050further comprises: (a) a housing 1082 that defines an interior space1084A for receiving a data cartridge 224 and an opening 1084B throughwhich a cartridge 224 is received into the interior space 1084A andthrough which a cartridge 224 is expelled from the interior space 1084A(sensor is located adjacent to the opening 1084B for use in determiningwhether a data cartridge 224 has been grasped and for determiningwhether a cartridge 224 is in a magazine 270); and (b) a rotary assembly1086 for selectively rotating the housing 1082. The rotary assembly 1086comprises: (a) a bracket 1088 that is attached to the carriage block1080; (b) a gear 1090 with a center bearing 1092 for attaching thebracket 1088 to the gear 1090 so as to allow relative rotationalmovement between the bracket 1088 and the gear 1090, and with an outergear ring 1094 that is fixed to the housing 1082; (c) a DC motor 1096for providing a rotational motive force that is used to rotate thehousing 1082 about an axis defined by the center bearing 1092, the DCmotor 1096 is attached the housing 1082 by a bracket 1098; (d) a pinion1100 that is attached to the spindle of the DC motor 1096 and engagesthe outer gear ring 1094. As will be appreciated by one skilled in theart, a rotational motive force produced by the DC motor 1096 istransmitted to the outer gear ring 1094 by the pinion 1100. As aconsequence, the housing 1082 rotates relative to the carriage block1080 and about the axis 1096. A rotational sensor 1102 that is attachedto the housing 1082 cooperates with a flag 224 that is associated withthe bracket 1088 to providing information on the rotational position ofthe housing 1082.

With reference to FIG. 34A, due to orientation of the drives 180 and theorientation of a cartridge 224 in a magazine 270 supported by themagazine picker 880, the rotary assembly 1086 must be able to rotate thehousing 1082 through a range 1108 of a least ninety degrees locatedbetween a vertical plane 1110 and a horizontal plane 1112 to transfer acartridge 224 between one of the drives 180 and a magazine 270 supportedby the magazine picker 880. In the illustrated embodiment, the rotaryassembly 1086 is able to rotate the housing 1082 through an additionalrange 1114 of about forty-five degrees. The ability to traverse a totalrange of approximately 135 degrees allows a bar-code reader 1120associated with the housing 1082 to read bar codes associated withmagazines 270 located on shelves 328A and shelves 328B, i.e., magazines270 located on both sides of the magazine transport 212 and cartridgetransport 214. The range of the rotary assembly 1086 can be furtherincreased if, for example, an additional drive or drives 180 werelocated on the opposite side of the library 202 from the drives 180. Thehousing 1082 comprises a top side 1118A, bottom side 1118B, first side1118C, second side 1118D, and back side 1118E. Associated with the backside 1118E is a bar code reader 1120 that is used to read a bar codelabel that is associated with and identifies a magazine 270 that islocated on a shelf in the shelf system 208 and a bar label that isassociated with a data cartridge magazine 270 located in a magazine 270.The barcode reader 1120 has an aperture 1122 with a field of view thatextends through the interior space 1084A of the housing 1082 and outthrough the opening 1084B defined by the housing 1082. FIG. 34Billustrates the ability of the rotary assembly 1086 and the bar codereader 1120 to read a bar code that identifies a first magazine 1124Athat is associated with the shelving 328A and a bar code that identifiesa second magazine 1124B that is associated with the shelving 328B. Withrespect to the magazines 1124A, 1124B disclosed herein and the commonorientation of all of the magazines 270 in the library 202, the bar codelabel associated with the magazine 1124A is situated in one of therecesses 290A, 290B and the bar code label associated with the magazine1124B is situated in the other of the recesses 290A, 290B. As FIG. 34Balso illustrates, the rotary assembly 1086 and the bar code reader 1120are also capable of reading a bar code label that is attached to an endface 1126 of a cartridge 224. In some cases, the horizontal transportunit 1052 must also be used to appropriately position the bar codereader 1120 to read a bar code label associated with a magazine 270 orwith a cartridge 224. In an alternative embodiment, the bar code readercan be located in a different location on the housing 1082. In yet otherembodiments, separate bar code readers can also be employed; one to reada bar code that identifies a magazine 270 and one to read a bar codethat identifies a cartridge 224. If two bar code readers are employed,the bar code reader for reading the bar code that identifies a magazine270 can be located elsewhere than the cartridge transport unit 1050(e.g., with the magazine picker 880). In other embodiments of thepresent invention, at least one sensor, such as an alternative reader orreaders, can be used to identify alternative identification forcartridges 224 and/or magazines 270. For instance, if an RFID (RadioFrequency Identification) tag is used to identify a magazine 270 orcartridge 224, an appropriately situated sensor or sensors can beassociated with the cartridge transport 214, magazine transport 212, orother appropriate element in the library 202.

With reference to FIGS. 33E and 33G-33I, the housing 1082 is capable ofaccommodating data cartridges of different dimensions. Morespecifically, the housing 1082 is capable of accommodating cartridgesthat have different heights, i.e., the perpendicular distance betweenthe two, parallel surfaces of the cartridge with the greatest surfaceareas. In the illustrated embodiment, the housing 1082 is capable ofaccommodating an LTO, SAIT or DLT tape cartridge 224, 240 or 254. LTOand SAIT tape cartridges 224, 240 have substantially the same height.The DLT tape cartridge 254, however, has a height that is greater thanthe heights of the LTO and SAIT tape cartridges 224, 240. With theforegoing in mind, the housing 1082 comprises a top half 1130A and abottom half 1130B that is attached to the top half 1130A to form thehousing 1082. Adaptively attached to the top half 1130A is plate 1132.To elaborate, the top half 1130A comprises: (a) screw holes 1134A,1134B, 1134C and 1134D each for receiving a screw, such as screw 1136;(b) spring towers 1138A, 1138B, 1138C and 1138D that each house aspring. The plate 1132 comprises: (a) retaining screw posts 1140A,1140B, 1140C and 1140D that each receive and retain a screw that passesthrough the corresponding one of the screw holes 1134A-1134D; and (b)spring seats 1142A, 1142B, 1142C and 1142D, each for supporting one endof a spring, such as spring 1144. The other end of each spring isreceived in the spring towers 1138A-1138D. The plate 1132 also comprisesa ramp 1146 that is disposed adjacent to the opening 1084B to facilitatethe insertion of data cartridges 224 into the interior space 1084A. Inoperation, the plate 1132 and the interior surface of the bottom side1118B are separated from one another when there is no cartridge 224 inthe interior space 1084A by a distance that is only slightly greaterthan the height of an LTO or SAIT tape cartridge 224, 240. When an LTOor SAIT tape cartridge 224, 240 is located in the interior space 1084A,the plate 1132 and the interior surface of the bottom side 1118B remainseparated by approximately the same distance as when there was nocartridge 224 in the interior space 1084A. In addition, the plate 1132and interior surface of the bottom side 1118B operate to constrain themovement of the cartridge 224 in one dimension, i.e., the heightdimension. When a DLT cartridge 254 is inserted into the interior space1084A, the greater height of the cartridge 254 displaces the plate 1132towards the top side 1118A of the housing and compresses the springs.Again, the plate 1132 and the interior surface of the bottom side 1118Bconstrain the movement of the cartridge 254 in one dimension, i.e., theheight dimension. When the DLT cartridge 254 is removed from theinterior space 1084A, the springs operate to return the plate 1118B tothe position at which it is separated from the interior surface of thebottom side 1118B by a distance that is slightly greater than the heightof an LTO or SAIT cartridge 224, 240.

The plate 1132 further comprises a flag 1148 that cooperates with adetector 1150 to indicates when a DLT tape cartridge 254 has beenreceived in the interior space 1084A. In operation, when a DLT cartridge254 is received in the interior space 1084A, the displacement of theplate 1132 causes the flag 1148 to pass through a slot 1152 in the tophalf 1130A and engage the detector 1150. The detector 1150 is located ona circuit board 1154 that is mounted to the top side 1118A of thehousing and that includes control circuitry for the rotary assembly 1086and the picker 880.

With reference to FIGS. 33K-33N, the cartridge transport unit 1050comprises: (a) a grasper assembly 1160 that is used to grasp a cartridge224; and (b) a linear drive assembly 1162 for moving a portion of thegrasper assembly 1160 to move a cartridge 224 into and out of theinterior space 1084A of the housing 1082. The grasper assembly 1160comprises: (a) the plate 1132 and the interior surface of the bottomside 1118B of the housing 1082, which cooperate with one another toconstrain a data cartridge 224 in a first dimension, i.e., the heightdimension 226A, 226B; (b) a picker assembly 1164 and the interiorsurface of the back side 1118E of the housing 1082, which cooperate withone another to constrain a cartridge 224 in a second dimension, i.e.,the depth dimension 230A, 230B between the ends of the cartridge 224;and (c) the interior surface of the first side 1118C of the housing 1082in combination with an interior wall 1166 of the housing 1082 and thepicker assembly 1164 to constrain a cartridge 224 in a third dimension,i.e., the width dimension 228A, 228B.

The picker assembly 1164 comprises: (a) a finger/thumb assembly 1168that is used in grasping a cartridge 224; and (b) a finger actuationassembly 1170 that is used to place a finger 1202 associated with thefinger/thumb assembly 1168 in a desired orientation for extracting adata cartridge 224 from a magazine 270, inserting a data cartridge 224into a magazine 270, extracting a data cartridge 224 from a drive 180,and inserting a data cartridge 224 into a drive 180.

The linear drive assembly 1162 operates to linearly move thefinger/thumb assembly 1168 to pull a cartridge 224 into the interiorspace 1084A of the housing 1082 and to expel a cartridge 224 from theinterior space 1084A of the housing 1082. The linear drive assembly 1162comprises: (a) a lead screw 1174 that is supported by the housing 1082;(b) a DC motor 1176 for providing a rotational motive force for movingthe finger/thumb assembly 1168, the motor 1176 is attached to a bracket1178; (c) a pinion 1180 that is attached to the spindle of the DC motor1176; (d) an idler gear 1182 that interfaces with the pinion 1180; (e) alead screw gear 1184 that interfaces with the idler gear 1182 and isattached to one end of the lead screw 1174. The finger/thumb assembly1168 comprises a nut portion 1188 that resides on the lead screw 1174and a guide tongue 1190 that is attached to the nut portion 1188 andresides in a groove 1192, a side of which is formed by the interior wall1166. When the motor 1176 produces a rotational motive force, thefinger/thumb assembly 1168 is displaced along the lead screw 1174.Typically, the displacement is associated with moving a cartridge 224into the interior space 1084A or expelling a cartridge 224 from theinterior space 1084A. Associated with the finger/thumb assembly 1168 isa flag 1194 that cooperates with a detector 1196 to indicate when thefinger/thumb assembly 1168 has been fully retracted into the interiorspace 1084A of the housing 1082. In addition, the detector 1196 is usedin combination with an encoder associated with the motor 1176 to providepositional information on the finger/thumb assembly 1168.

The finger/thumb assembly 1168 further comprises: (a) mounting block1200; (b) a finger 1202 that is pivotally attached to the mounting block1200 via a finger pivot shaft 1204; (c) finger cam 1206 that is attachedto the finger 1202 and includes a first and second finger cam legs1208A, 1208B; (d) a finger return spring assembly 1210 that is attachedto the pivot shaft 1204 and operates to bias the finger 1202 towards adata cartridge 224; and a thumb 1212 that limits the movement of thefinger 1202 towards a cartridge 224 and also assists in pushing acartridge 224 out of the interior space 1084A. It should be appreciatedthat in embodiments of a magazine-based data cartridge library 202 thatoperate only on cartridges, such as a SAIT tape cartridge 240, with twogripper notches, such as notches 250A and 250B, a cartridge may begrasped between a pair of movable elements.

The finger actuation assembly 1170 comprises: (a) a bracket 1216 that ismounted to the housing 1082; (b) a picker 1218 that is pivotallyattached to the bracket 1216; (c) a picker cam 1220 that engages thefinger cam surface 1206 to place the finger 1202 in desired orientationsfor particular insertion and extraction operations, with the picker cam1220 comprising first and second picker cam legs 1222A, 1222B; (d) asolenoid 1224 that is used to rotate the picker 1218 and comprises aplunger 1226 that is attached to the picker 1218; and (e) a stop 1228that limits the rotation of the picker 1218 in one direction.

Also associated with the cartridge transport 214 is a wall structure1230 that serves to counteract the rotation of a cartridge 224 thatoccurs during extraction of the cartridge 224 from a magazine 270 orinsertion the cartridge 224 into the magazine 270 due to the manner inwhich the picker assembly 880 engages the cartridge 224. It should alsobe appreciated that the cartridge transport 214 and the magazinetransport 212 both comprise the elevator 750. As a consequence, elementsof the cartridge transport 214 other than the elevator 750 and elementsof the magazine transport 212 other than the elevator 750 are moved inunison by the elevator 750. This relationship makes possible bulk loadand bulk unload operations. However, as will be appreciated by oneskilled in the art, in other embodiments a cartridge transport and amagazine transport can each have an elevator that is capable ofindependent operation. Further, the operational ranges of the elevatorscan be substantially the same or different. Further, a cartridgetransport with fewer actuators than those associated with the cartridgetransport 214 is feasible. For example, a cartridge transport withelements that are functionally equivalent to all of the elements of thecartridge transport 214 described above, except for the elevator, couldbe mounted adjacent to a drive 180. In such an embodiment, a magazinetransport would bring a magazine 270 into the operational range of thecartridge transport for the loading of cartridges 224 into the magazine270 by the cartridge transport and the unloading of a cartridge 224 fromthe magazine 270 by the cartridge transport. In another possibleembodiment, a cartridge transport with elements that are functionallyequivalent to all of the elements of the cartridge transport 214described above, except the elevator 750 and the horizontal transport1052, could be mounted adjacent to a drive 180. In such an embodiment,the magazine transport would operate to bring magazines into the generaloperational range of the cartridge transport and the magazine pickerwould be used to position a specific slot of a magazine 270 for theloading and unloading of cartridges 224 by the cartridge transport. Inany event, a cartridge transport is a device that is capable of moving adata cartridge 224 between a magazine 270 and a drive 180.

With reference to FIGS. 35A-35C, the operation of the cartridgetransport 214 in moving a data cartridge 1232 from a magazine 270 to adrive 1236 is generally described. With reference to FIG. 35A, themagazine transport 212 has been used to move the magazine 270 from astorage location, such as a shelf of the shelf system 208 or the entryexit port 120, to the support structure 884. To elaborate, the magazinetransport 212 has, if necessary, used the elevator 750 to position themagazine picker 880 and the support structure 884 adjacent to thewhatever storage location was supporting the magazine 270. In thisregard, one of the detectors 982, 984 was used to position the magazinepicker 880 and the support structure 884. Further, the rotary assembly1086 has likely been used to place the housing 1082 and the associatedbar-code reader 1120 at an orientation that allows the bar-code reader1120 to read a bar-code label associated with the magazine 270 toconfirm that the appropriate magazine 270 is being accessed. Once themagazine picker 880 and support structure 884 were positioned adjacentto the storage location that was supporting the magazine 270, themagazine picker 880 and support structure 884 were used to move themagazine 270 from the storage location to the support structure 884.During the moving of the magazine 270 onto the support structure 884,the rotary assembly 1086 has been used to place housing 1082 and theassociated bar-code reader 1120 at an orientation that allowed the barcode reader 1120 to read the bar-code labels associated with thecartridges 1232 and 224 in the magazine 270 to identify the desiredcartridge, namely, cartridge 1232. In this regard, the rotary assembly1086 is typically used to place the housing 1082 in the verticalorientation shown in FIG. 35A or at an angle that is between thevertical and horizontal planes 1236A, 1236B so that the bar-code reader1120 can read the bar-codes associated with cartridges 1232 and 224 inthe magazine 270.

With reference to FIG. 35A, after the magazine 270 has been positionedon the support structure 884 as shown in FIG. 35A or during the timewhen the magazine 270 is being positioned on the support structure 884,the horizontal transport unit 1052 and the rotary assembly 1086 areused, as needed, to position the opening 1084B of the housing 1082 toreceive the data cartridge 1232. The linear drive assembly 1162 and thepicker assembly 1164 are then used to draw the cartridge 1232 into theinterior space 1084A of the housing 1082. The detector 1196 is used todetermine when the cartridge 1232 has been fully retracted into theinterior space 1084A of the housing 1082. At this point, it should beappreciated that: (a) the magazine 270 has oriented the cartridge 1232(an LTO magazine 270 and cartridge 224) such that the face 226A of thecartridge 1232 with the greatest surface area lies in a vertical plane;and (b) that in extracting the cartridge 1232 from the magazine 270, thecartridge 1232 has been vertically displaced within the vertical plane.

At some point in retracting the cartridge 1232 into the housing 1082,the cartridge 1232 and elements of the cartridge transport 214 aresituated so as not to interfere with any movement of the magazine 270.At this point, the magazine picker 880 can be used to transfer themagazine 270 from the support structure 884 to its original storagelocation or to another storage location, which may require the use ofthe elevator 750. Alternatively, the magazine 270 can be left on thesupport structure 884. Leaving the magazine 270 on the support structure884 is desirable if, for example, a “bulk load” operation is to beperformed.

In any event, after the picker assembly 1164 has engaged the cartridge1232, the rotary assembly 1086 is used to rotate the housing 1082 andthe grasped cartridge 1232 from the vertical orientation shown in FIG.35A to the horizontal orientation shown in FIG. 35B. Typically, therotary assembly 1086 rotates the housing 1082 after the cartridge 1232has been completely retracted into the housing 1082. However, in certaincircumstances, it is possible for the rotary assembly 1086 to rotate thehousing 1082 during the period of time when the cartridge 1232 is beingretracted into the housing 1082. For cartridges 224 located in the slotsat or near the ends of the magazine 270, rotation of the housing 1082 tothe horizontal orientation shown in FIG. 35B may also require that thehorizontal transport unit 1052 horizontally and linearly translate thehousing 1082 towards the center of the magazine 270 to prevent thehousing 1082 from coming into contact with a shelf of the shelf system208 or other element of the library 202. At this point, it should beappreciated that the cartridge 1232 has been rotated about a horizontalaxis and about a horizontal axis that is parallel to the face of thecartridge 1232 with the greatest surface area, such as the face 226A.

With reference to FIG. 35C, the horizontal transport unit 1052 is used,as needed, to linearly and horizontally translate the housing 1082 andthe cartridge 1232 in the direction required to insert the cartridge1232 into the drive 1236. In addition, the elevator 750 and detector 984(which operates in this instance to detect the flag 632 associated withthe drive 1236) have been used, as needed, to position the housing 1082so that when the housing 1082 is horizontally disposed as shown in FIGS.35B and 35C, the opening of the housing 1082 is aligned with thereceptacle, such as the receptacle 186 from FIG. 5A, of the drive 1236.The elevator 750 and detector 984 can be used to position the housing1082 for insertion of the cartridge 1232 into the drive 1236 at any timeafter the magazine 270 has been loaded onto the support structure 1084.Once the opening 1084B of the housing 1082 has been aligned with thereceptacle of the drive 1236, the cartridge 1232 is inserted into thedrive 1236. In this regard, the linear drive assembly 1162 is used toexpel the cartridge 1232 from the housing 1082 and into the drive 1236.The linear drive assembly 1162 typically begins expelling the cartridge1232 after the opening 1084B has been disposed substantially adjacent tothe receptacle of the drive 1236. However, the expulsion process cancommence earlier. However, there may be risks associated with commencingthe expulsion process earlier.

At this point, if the magazine 270 is still associated with the supportstructure 884, a bulk load operation can be performed, if desired. In abulk load operation, the housing 1082 is repositioned using thehorizontal transport unit 1052 and the rotary assembly 1056, as needed,so that a second cartridge 1233 in the magazine 270 can be grasped. Thesecond cartridge 1233 is grasped and then oriented for insertion into asecond drive (not shown) in the same manner as previously described withrespect to the cartridge 1232. Further, the elevator 750 is used toposition the housing 1082 for insertion of the second cartridge 1233into the second drive. The disclosed bulk load operation can be used totransfer a desired number of cartridges 224 from a magazine 270 for usewith a commensurate number of drives 180. [0267] It should also be notedat this point that the process for moving a data cartridge, such ascartridge 1232, from a magazine 270 to a drive, such as drive 1236,involved the use of the magazine picker 880 to move a magazine 270 ontothe support structure 884 such that the magazine 270 was no longerassociated with a storage location and completely supported by thesupport structure 884. If only one cartridge 1232 is to be moved from amagazine 270 to a drive 1236, an alternative process potentially avoidsthe need to fully extract the magazine 270 from its storage location. Inthis process, the magazine picker 880 terminates the extraction of amagazine 270 from a storage location after the desired cartridge 1232has been exposed and is capable of being grasped. In one embodiment, thehorizontal transport unit 1052 is used to position the housing 1082 asclose to the storage location from which the magazine 270 is to beextracted as is feasible. Further, the rotary assembly 1086 places thehousing 1082 in the vertical orientation shown in FIG. 35B. With thehousing 1082 positioned by the horizontal transport unit 1052 and therotary assembly 1086 in this manner, the desired cartridge 1232 can begrasped quickly once it is exposed. To elaborate, the signal provided bythe bar-code reader 1120 once the desired cartridge 1232 is exposed anddetected is used to terminate the operation of the magazine picker 880such that the desired cartridge 1232 is positioned underneath theopening 1084B of the housing 1082. It should be appreciated that if theslot in the magazine 270 in which the desired cartridge 1232 is locatedis known beforehand, this information can be used to terminate theoperation of the magazine picker 880 such that the desired cartridge1232 is positioned underneath the opening 1084B of the housing 1082. Inany event, extraction of the cartridge 1232 from the magazine 270proceeds as previously described. However, if the magazine 270 has notbeen completely extracted from its storage location, a decision must bemade as to whether to proceed with the extraction of the magazine 270from its storage location or proceed to reinsert the magazine 270 intoits storage location because the elevator 750 cannot be used to move thegrasped cartridge 1232 to a drive 1236 until the magazine 270 issubstantially removed from its storage location or substantiallyinserted into its storage location. In either case, once the magazine270 has been substantially removed from its storage location orsubstantially returned to its storage location, the grasped cartridge1232 is moved to a drive 1236 as previously described.

The operation of the cartridge transport 214 in moving the datacartridge 1232 from a drive 1236 to a magazine 270 is generallydescribed with reference to FIGS. 35A-35C. With reference to FIG. 35C,the elevator 750 and the detector 984 have been used to grossly positionthe housing 1082 adjacent to the drive 1236, which holds the cartridge1232. Further, the horizontal transport unit 1052 and the rotaryassembly 1086 have been used, as needed, to orient the housing 1082 asshown in FIG. 35C. Consequently, through the operation of the elevator750, horizontal transport 1052 and the rotary assembly 1086, as needed,the housing 1082 has been positioned to receive the cartridge 1232 fromthe drive 1236. Although FIG. 35C shows the magazine 270 on the supportstructure 884, the magazine 270 may or may not be associated with thesupport structure 884 when the housing 1082 is positioned to receive thecartridge 1232 from the drive 1236. If the magazine 270 is associatedwith the support structure 884, a “bulk unload” operation can beperformed, if desired. In any event, the linear drive assembly 1162 andpicker assembly 1164 operate to extract the cartridge 1232 from thedrive 1236.

With reference to FIGS. 35B and 35C, once the cartridge 1232 issubstantially clear of the drive 1236, the horizontal transport unit1052 (as needed) and the rotary assembly 1086 are used to position thehousing 1082 and the grasped cartridge 1232 for insertion into themagazine 270. Even though the housing 1082 and the grasped cartridge1232 are being position for insertion of the cartridge 1232 into themagazine 270, it should be appreciated that the magazine 270 may or maynot be associated with the support structure 1084 during thispositioning of the housing 1082 and the grasped cartridge 1232. At thispoint, it should be appreciated that the cartridge 1232 has been rotatedabout a horizontal axis and about a horizontal axis that is parallel tothe face, such as the face 226A, of the cartridge 1232 with the greatestsurface area. After the cartridge 1232 is substantially clear of thedrive 1236, the elevator 750 and one of the detectors 982, 984 is usedto position the magazine picker 880 and the support structure 884adjacent to the storage location of the magazine 270.

After the housing 1082 and the grasped cartridge 1232 have beenpositioned as shown in FIG. 35A, the cartridge 1232 is positioned forinsertion into the magazine 270. Although FIG. 35A shows the magazine270 as being on the support structure 884, the magazine 270 may not yetbe associated with the support structure 884. In any event, beforeinsertion of the cartridge 1232 into the magazine 1236 can beaccomplished, the magazine 270 is positioned on the support structure884 as shown in FIG. 35A. If the magazine 270 was not associated withthe support structure 884 when the housing 1082 was positioned toreceive the cartridge 1232 from the drive 1236, the magazine 270 isextracted from its storage location after the elevator 750 hasappropriately positioned the support structure 884 adjacent to thestorage location of the magazine 270. Once the housing 1082 and graspedcartridge 1232 and the magazine 270 are positioned as shown in FIG. 35A,the linear drive assembly 1162 and the picker assembly 1164 operate toexpel the cartridge 1232 from the housing 1082 into the magazine 270. Itshould be noted at this point that in inserting the cartridge 1232 intothe magazine 270: (a) the cartridge 1232 was oriented such that theface, such as the face 226A, of the cartridge 1232 with the greatestsurface area lay in a vertical plane; and (b) that the cartridge 1232was vertically displaced within the vertical plane.

It should be noted that if the magazine 270 was associated with thesupport structure 884 when the housing 1082 was positioned to receivethe cartridge 1232 from the drive 1236, a “bulk unload” operation can beperformed in which the cartridge 1232 is returned to the magazine 270 asdescribed except that before the elevator 750 and magazine picker 880are used to return the magazine 270 to its storage location, theelevator 750, horizontal transport unit 1052, rotary assembly 1086 andgrasper assembly 1160 are used to move additional cartridges 224 fromother drives 180 to the magazine 270.

It should also be noted that in the situation in which the magazine 270is not associated with the support structure 884 when the housing 1082is positioned to receive a cartridge 224 from a drive 180, a process inwhich a cartridge 224 can be returned to a magazine 270 in many caseswithout fully extracting the magazine 270 from its storage location canbe implemented. To elaborate, the if the magazine 270 was not associatedwith the support structure 884 when the housing 1082 was positioned toreceive the cartridge 1232, the magazine 270 must be extracted from itsstorage location after the cartridge 1232 has been extracted from thedrive 1236 and the elevator 750 has positioned the support structure 884adjacent to the storage location for the magazine 270. In this process,the magazine picker 880 terminates the extraction of a magazine 270 froma storage location after the desired cartridge 1232 has been exposed andis capable of being grasped. In one embodiment of the process, themagazine picker 880 terminates the extraction of a magazine 270 from itsstorage location after the slot in the magazine 270 that is to store thecartridge 1232 has been exposed. In one embodiment, the horizontaltransport unit 1052 is used to position the housing 1082 as close to thestorage location from which the magazine 270 is to be extracted as isfeasible. Further, the rotary assembly 1086 places the housing 1082 inthe vertical orientation shown in FIG. 35B. With the housing 1082positioned by the horizontal transport unit 1052 and the rotary assembly1086 in this manner, the cartridge 1232 can be inserted into themagazine 270 shortly after the slot in the magazine 270 that is toretain the cartridge 1232 is exposed. To elaborate, signals provided bythe operation of the center position flag 920 in conjunction with thefirst sensor assembly 942 and an encoder associated with the motor 914are used to determine when the slot in the magazine 270 in which themagazine 270 is to be placed is exposed and uses these signals toterminate the operation of the magazine picker 880 such that the desiredcartridge 1232 is positioned underneath the opening 1084B of the housing1082. At this point, the linear drive assembly 1162 and the pickerassembly 1164 operate to insert the cartridge 1232 into the magazine270. Once the cartridge 1232 is sufficiently inserted into the magazine270, the magazine picker 880 operates to return the magazine 270 to itsstorage location.

It should also be appreciated that the magazine 270 from which acartridge 224 is extracted does not have to be the magazine 270 to whichthe cartridge 224 is later returned.

If desired, the cartridge transport 214 can also be used to move thecartridge 1232 from one drive 180 to another drive 180. To move thecartridge 1232 from one drive 180 to another drive 180, the elevator750, horizontal transport unit 1052, and rotary assembly 1086 are usedto position the housing 1082 as shown in FIG. 35C to receive the datacartridge 1232 from the drive 1236. Once the housing 1082 has beenpositioned to receive the data cartridge 1232 from the drive 1236, thelinear drive assembly 1162 and the picker assembly 1164 are used toextract the cartridge 1232 from the drive 1236. After the cartridge 1232has been extracted from the drive 1236, the elevator 750 is used toposition the housing 1082 and the grasped cartridge 1232 for insertioninto another one of the drives 180.

With reference to FIGS. 36A-36G, having generally described the use ofthe cartridge transport 214 in moving a data cartridge 224 between amagazine 270 and a drive 180, the operation of the picker assembly 1164(which is comprised of the finger/thumb assembly 1168 and the fingeractuation assembly 1170) and the linear drive assembly 1162 is describedwith respect to the: (a) picking or removing of a cartridge 224 from amagazine 270; and (b) loading of a previously grasped cartridge 224 intothe magazine 270. FIGS. 36A-36F, when viewed in sequence, illustrate theoperation of the picker assembly 1164 and the linear drive assembly 1162in picking an LTO cartridge magazine 270 with a picker notch 234A from amagazine 270. With reference to FIG. 36A, (a) the elevator 750,horizontal transport unit 1052, and rotary assembly 1086 have, asneeded, positioned the housing 1082 so that the opening 1084B isadjacent to the cartridge 1240; (b) the linear drive assembly 1162 haspositioned the finger/thumb assembly 1168 within the housing 1082; and(c) the finger actuation assembly 1164 has positioned the picker 1218 sothat the picker 1218 essentially has no effect upon the finger 1202during the extraction operation. More specifically, the solenoid 1224has fully extended the plunger 1226. As a consequence, the picker 1218is positioned such that further rotation is prevented by the stop 1228.

With reference to FIG. 36B, the DC motor 1176 of the linear driveassembly 1162 has been used to displace the finger/thumb assembly 1168along the lead screw 1174 and towards the cartridge 1240. At this point,the finger 1202 has engaged the top end 230A of the cartridge 1240. Withreference to FIG. 36C, as the linear drive assembly 1162 displaces thefinger/thumb assembly 1168 further towards the cartridge 1240, theinteraction of the finger 1202 with the surfaces of the cartridge 1240causes the finger 1202 to rotate away from the cartridge 1240 such thatenergy is stored in the return spring 1210. With reference to FIGS. 36Cand 36D, further displacement of the finger/thumb assembly 1168 towardsthe cartridge 1240 eventually results in the finger 1202 reaching thenotch 234A. At this point, the energy stored in the return spring 1210causes the finger 1202 to engage the notch 234A. With the notch 234Aengaged, the cartridge 1240 can now be extracted from the magazine 270.With reference to FIG. 36E, after the notch 234A has been engaged, thelinear drive assembly 1162 operates so as to displace the finger/thumbassembly 1168 and the cartridge 1240 away from the magazine 270. Thewall 1230 serves to counteract rotation of the cartridge 1240 during theextraction. The linear drive assembly 1162 continues the displacement ofthe finger/thumb assembly 1168 and the cartridge 1240 away from themagazine 270 until the cartridge 1240 is fully within the housing 1082,as shown in FIG. 36F.

FIGS. 36F, 36E, 36D and 36G illustrate the operation of the pickerassembly 1164 and the linear drive assembly 1162 in loading the LTOcartridge 270 into the magazine 270. With reference to FIG. 36F, (a) theelevator 750, horizontal transport unit 1052, and rotary assembly 1086have, as needed, positioned the housing 1082 so that the opening 1084Bis adjacent to the slot of the magazine 270 which is to hold thecartridge 1240; (b) the linear drive assembly 1162 and the finger/thumbassembly 1168 are operating to retain the cartridge 1240 within thehousing 1082; and (c) the finger actuation assembly 1164 has positionedthe picker 1218 so that the picker 1218 will not have an effect upon thefinger 1202 during insertion of the cartridge 1240 into the magazine270. More specifically, the solenoid 1224 has fully extended the plunger1226. As a consequence, the picker 1218 is positioned such that furtherrotation is prevented by the stop 1228.

With reference to FIG. 36E, the linear drive assembly 1162 has been usedto displace the finger/thumb assembly 1168 and the cartridge 1240 alongthe lead screw 1174 and towards the magazine 270. With reference to FIG.36D, the linear drive assembly 1162 has continued to displace thefinger/thumb assembly 1168 and the cartridge 1240 along the lead screw1174 and towards the magazine 270 until the cartridge 1240 is fullyloaded into the magazine 270. During the displacement of the cartridge1240 towards the magazine 270, the wall 1230 has served to counteractrotation of the cartridge 1240. At this point, the picker cam surface1220 of the picker 1218 is disposed between the finger cam 1206 of thefinger 1202 and the pivot shaft 1204 of the finger 1202. To disengagethe finger 1202 from the notch 234A of the cartridge 1240 and releasethe cartridge 1240, the solenoid 1224 is operated so as to retract theplunger 1226 and thereby rotate the picker 1218. Rotation of the picker1218 pushes the finger 1202 away from the cartridge 1240 as shown inFIG. 36G. At this point, loading of the cartridge 1240 into the magazine270 is complete.

FIGS. 37A-37D, when viewed in sequence, illustrate the operation of thepicker assembly 1164 and the linear drive assembly 1162 in loading theLTO cartridge 1240 into a drive 1246. With reference to FIG. 37A, (a)the elevator 750, horizontal transport unit 1052, and rotary assembly1086 have, as needed, positioned the housing 1082 so that the opening1084B is adjacent to the receptacle, such as the receptacle 186 fromFIG. 5A, of the drive 1246; (b) the linear drive assembly 1162 and thefinger/thumb assembly 1168 are operating to retain the cartridge 1240within the housing 1082; and (c) the finger actuation assembly 1164 haspositioned the picker 1218 so that the picker 1218 will not have aneffect upon the finger 1202 at this point in time. More specifically,the solenoid 1224 has fully extended the plunger 1226. As a consequence,the picker 1218 is positioned such that further rotation is prevented bythe stop 1228.

With reference to FIG. 37B, the linear drive assembly 1162 has been usedto displace the finger/thumb assembly 1168 and the cartridge 1240 alongthe lead screw 1174 and towards the drive 1246. In addition, before thedisplacement of the finger/thumb assembly 1168 along the lead screw 1174by the linear drive assembly 1162 reaches a point at which the fingercam 1206 of the finger 1202 could contact with the picker cam surface1220, the finger actuation assembly 1164 has positioned the picker 1218the picker 1218 so that the picker cam surface 1220 will cause thefinger 1202 to rotate away from the cartridge 1240 and release thecartridge 1240 earlier than occurs during the loading of a cartridge1240 into a magazine 270. More specifically, the solenoid 1224 has beenoperated so as to fully retract the plunger 1226 and thereby positionthe picker cam surface 1220 of the picker 1218 to interact with thefinger cam 1206 of the finger 1202 to release the cartridge 1240 earlierthan in the magazine loading operation. With reference to FIGS. 37C and37D, further displacement of the picker/thumb assembly 1168 by thelinear drive assembly 1162 eventually causes the picker cam surface 1220to engage the finger cam 1206. After the picker cam surface 1220 hasengaged the finger cam 1206, further displacement of the picker/thumbassembly 1168 towards the drive 1246 results in the picker cam surface1220 applying a force to the finger 1202, via the finger cam 1206, thatcauses the finger 1202 to rotate about the pivot shaft 1204 and awayfrom the cartridge 1240, thereby releasing the cartridge 1240 to thedrive 1246. Comparison of FIG. 37C to FIG. 36G shows that the operationof the finger actuation assembly 1164 in the loading of the cartridge1240 into the drive 1246 causes the finger 1202 to release the cartridge1240 earlier than in the case of loading the cartridge 1240 into themagazine 270.

FIGS. 37E, 37F, 37G and 37A, when viewed in sequence, illustrate theoperation of the picker assembly 1164 and the linear drive assembly 1162in picking an LTO cartridge 1244 with a picker notch 234A from the drive1246. With reference to FIG. 37E, (a) the elevator 750, horizontaltransport unit 1052, and rotary assembly 1086 have, as needed,positioned the housing 1082 so that the opening 1084B is adjacent to thedrive 1246; (b) the linear drive assembly 1162 has positioned thefinger/thumb assembly 1168 within the housing 1082; and (c) the fingeractuation assembly 1164 has positioned the picker 1218 so that thepicker 1218 essentially has no effect upon the finger 1202 during theextraction operation. More specifically, the solenoid 1224 has fullyextended the plunger 1226. As a consequence, the picker 1218 ispositioned such that further rotation is prevented by the stop 1228.

With reference to FIG. 37F, the DC motor 1176 of the linear driveassembly 1162 has been used to displace the finger/thumb assembly 1168along the lead screw 1174 and towards the drive 1246. At this point, thefinger 1202 has engaged the cartridge 1240 and the interaction of thefinger 1202 with the surfaces of the cartridge 1240 has caused thefinger 1202 to rotate away from the cartridge 1240 such that energy isstored in the return spring 1180. With reference to FIG. 37G, furtherdisplacement of the finger/thumb assembly 1168 towards the cartridge1240 eventually results in the finger 1202 reaching the notch 234A. Atthis point, the energy stored in the return spring 1180 causes thefinger 1202 to engage the notch 234A. With the notch 234A engaged, thecartridge 1240 can now be extracted from the drive 1246. With referenceto FIG. 37A, after the notch 234A has been engaged, the linear driveassembly 1162 operates so as to displace the finger/thumb assembly 1168and the cartridge 1240 away from the drive 1246. The linear driveassembly 1162 continues the displacement of the finger/thumb assembly1168 and the cartridge 1240 away from the magazine 270 until thecartridge 1240 is fully within the housing 1082, as shown in FIG. 37A.

It should be appreciated that many of the elements of the library 202employ linear or rotary actuators. Generally, for elements that employ alinear actuator, designs are feasible that employ a rotary actuator.Similarly, for elements that employ a rotary actuator, designs arefeasible that employ a linear actuator. Further, the elements of thelibrary 202 that employ linear or rotary actuators are capable ofemploying electrical actuators. Other embodiments of the presentinvention can employ actuators that utilize hydraulic or pneumaticactuators. In addition, many of the electrical motors utilized in thelibrary 202 are DC motors. As one skilled in the art will appreciate,other types of electrical motors are feasible.

With reference to FIG. 38, the relationship between the space occupiedby shelved magazines 270 in the library 202 to the other elements of thelibrary 202 is described. A first magazine 1250A associated with a firstshelf 1252A of any one of the five columns of shelving 328A resides in avertical plane that is bounded by a first face 1254A that correspondswith the front face of the first magazine 1250A and a second face 1256Athat corresponds with the rear face of the first magazine 1250A and issubstantially parallel to the first face 1254A (a first magazine space).The first shelf 1252A is accessible for loading and unloading the firstmagazine 1250A at substantially where the first face 1254A is defined.The first magazine 125A is loaded and unloaded to and from the firstshelf 1252A via the magazine transport 212 and magazine picker 880.Similarly, a second magazine 1250B associated with a second shelf 1252Bof any one of the two columns of shelving 328B resides in a verticalplane that is bounded by a first face 1254B and a second face 1256B thatrespectively correspond to the front and rear surfaces of the secondmagazine 1250B (a second magazine space). As disclosed in FIGS. 28A and28B, the second shelf 1252B can reside in compartments 544A-544F withinthe user definable space 336. The second shelf 1252B is accessible forloading and unloading the second magazine 1250B at substantially wherethe first face 1254B is defined. The user definable space 336 can alsocomprise a drive 1260 wherein data cartridges can be loaded to and fromthe drive 1260 substantially where the first face 1254B is defined. Thedistance between the first and second planes 1254A, 1256A (or betweenthe first and second planes 1254B, 1256B) defines the minimum distancethat is needed between the first planes 1254A, 1254B (at least a portionof the space between these two planes 1254A, 1256A defining a magazinetransport space) for the magazine transport 212 to move a magazinewithin the library 202 without reorienting a magazine, such as the firstmagazine 1250A for example. Hence, the magazine transport space isbounded between the first face 1254A corresponding to the first shelf1252A, which is the interface of the magazine transport space and theface where the first shelf 1252A can receive the first magazine 1250A,and the first face 1254B corresponding to the second shelf 1252B, whichis the interface of the magazine transport space and the face where theuser definable space 336 can receive the second magazine 1250B. Thecloser the distance between the first planes 1254A, 1254B to the minimumdistance for the magazine transport 212, the more volume there is withinthe library 202 to accommodate more magazines 270 and/or more drives180. In the illustrated embodiment, the distance between the planes1254A, 1254B is less than twice the distance between the planes 1254A,1256A and approaches 130% of the distance of the distance between theplanes 1254A, 1256A. Further, the distance between the first and secondplanes 1254A, 1256A (or the distance between the first and second planes1254B, 1256B) is roughly equal to the distance between the front andrear surfaces 1258A, 1258B of the drive 1260, of the two columns ofdrives 180. This allows the two columns of drives 180 and shelving 1252Bto be positioned within the library 202 so as to efficiently utilize theavailable space within the library 202. It should also be appreciatedthat the magazine transport space overlaps with the magazine spaces orcan be slightly greater than the width of a magazine 270, such as thefirst magazine 1250A defined by the first and second face 1254A, 1256A.

In a magazine-based library 100 with a circular/cylindrical type layout,the magazine transport 108 travels in a space that is located betweentwo concentric “planes” or surfaces. Further, the magazines 270 aretypically located in one or more spaces that are each located betweentwo planes.

FIG. 39 illustrates the control system 218 for the library 202.Generally, the control system 218 is comprised of controller 1264 thatis capable with communicating with other controllers in the library 202that are associated with various electrical elements within the library202. More specifically, the controller 1264 is capable of communicatingwith: (a) a first and second entry/exit port controllers 1266A, 1266Bthat respectively control electrical elements associated with the firstand second entry/exit ports 368, 370; (b) a horizontal axis controller1268 that controls electrical elements associated with the horizontalaxis assembly 754 of the elevator 750; (c) a vertical axis controller1270 that controls electrical elements associated with the vertical axisassembly 752 of the elevator 750; (d) a short axis/magazine controller1272 that controls electrical elements associated with the horizontaltransport unit 1052, magazine picker 880, and magazine transport device900; (e) a rotation axis/picker axis controller 1274 that controlselectrical elements associated with the rotary 1086, the linear driveassembly 1162, and the picker assembly 1164; and (f) an environmentalcontroller 1276 that controls, among other things, the fans 220. Inaddition, the controller 1264 also communicates with elements associatedwith the operator interface 342. Further, the controller 1264 alsocommunicates with the QIP 668 associated with an drive bay assembly 540in the library via a Controller Area Network (CAN). Other controlsystems are also feasible.

The library 202 operates to read and/or write data on a recording mediumthat is located in a cartridge 224 that is stored in a magazine 270 thatis, in turn, stored on a shelf of the shelf system 208 or in anotherstorage location. Further, when the cartridge 224 is stored in themagazine 270, the cartridge 224 is oriented in the library 202 such thatthe face of the cartridge 224 with the greatest surface area, such asthe surface 226A used herein for illustrative purposes, lies in asubstantially vertical plane. Moreover, the cartridge 224 is oriented sothat the surface vector of the face 226A of the cartridge 224 with thegreatest surface area is substantially parallel to the direction inwhich the magazine picker 880 displaces the magazine 270. Further, whenthe cartridge picker 214 extracts/inserts the cartridge 224 from/intothe magazine 270, the cartridge picker 214 displaces the cartridge 224vertically within the noted vertical plane.

It should be appreciated that other embodiments of a magazine-based datacartridge library 202 are capable of operating on cartridges 224 thatare oriented when in storage so that the face 226A of the cartridge 224with the greatest surface area lies in a vertical plane, but the surfacevector of the face 226A lies substantially perpendicular to thedirection in which a magazine picker 880 displace the magazine 270storing the cartridge 224 and/or a cartridge picker 214 extracts/insertsthe cartridge 224 from/into the magazine 270 such that the magazine 270is displaced horizontally within the vertical plane.

FIG. 40A illustrates an alternative embodiment of a magazine 1280suitable for use in an alternative embodiment of a magazine-based datacartridge library relative to library 202. When the magazine 1280 isoperationally disposed on a shelf 1282 of the library 202, the magazine1280 holds a cartridge 1284 such that: (a) a face of the cartridge 1284with the greatest surface area 1286 lies in a vertical plane; (b) thesurface vector 1288 of the face 1286 is substantially perpendicular to adirection 1290 that the magazine 1280 is displaced by a magazine picker880; and (c) the cartridge 1284 is displaced in a vertical direction1292 by a cartridge picker 214 to insert/extract the cartridge 1284into/from the magazine 1280.

FIG. 40B illustrates an alternative embodiment of a magazine 1294suitable for use in an alternative embodiment of a magazine-based datacartridge library relative to library 202. Each of the features in FIG.40B that is substantially identical to a feature in FIG. 40A has beengive the same reference number as the feature in FIG. 40A. When themagazine 1294 is operationally disposed on a shelf 1282 of the library202, the magazine 1294 holds a cartridge 1284 such that: (a) a face 1286of the cartridge 1284 with the greatest surface area lies in a verticalplane; (b) the surface vector 1288 of the face 1286 is substantiallyparallel to a direction 1290 that the magazine 1294 is displaced by amagazine picker 880; and (c) the cartridge is displaced in a direction1292, a horizontal direction in the vertical plane in which the face1286 of the cartridge 1284 with the greatest surface area lies, by acartridge picker 214 to insert/extract the cartridge 1284 into/from themagazine 1294.

FIG. 40C illustrates an alternative embodiment of a magazine 1296suitable for use in an alternative embodiment of a magazine-based datacartridge library relative to library 202. Each of the features in FIG.40C that is substantially identical to a feature in FIG. 40A has beengive the same reference number as the feature in FIG. 40A. When themagazine 1296 is operationally disposed on a shelf 1282 of the library202, the magazine 1296 holds a cartridge 1284 such that: (a) a face 1286of the cartridge 1284 with the greatest surface area lies in a verticalplane; (b) the surface vector 1288 of the face 1286 is substantiallyperpendicular to a direction 1290 that the magazine 1296 is displaced bya magazine picker 880; and (c) the cartridge 1284 is displaced in ahorizontal direction 1292 in the vertical plane in which the face 1286of the cartridge 1284 with the greatest surface area lies, by acartridge picker 214 to insert/extract the cartridge 1284 into/from themagazine 1296.

FIG. 40D illustrates an alternative embodiment of a magazine 1298suitable for use in an alternative embodiment of a magazine-based datacartridge library relative to library 202. Each of the features in FIG.40D that is substantially identical to a feature in FIG. 40A has beengive the same reference number as the feature in FIG. 40A. When themagazine 1298 is operationally disposed on a shelf 1282 of the library202, the magazine 1298 holds a cartridge 1284 such that: (a) a face 1286of the cartridge 1284 with the greatest surface area lies in a verticalplane; (b) the surface vector 1288 of the face 1286 is substantiallyperpendicular to a direction 1290 that the magazine 1298 is displaced bya magazine picker 880; and (c) the cartridge 1284 is displaced in adirection 1292, a horizontal direction in the vertical plane in whichthe face 1286 of the cartridge 1284 with the greatest surface area lies,by a cartridge picker 214 to insert/extract the cartridge 1284 into/fromthe magazine 1298.

FIG. 40E illustrates a cross-section of alternative embodiment of amagazine 1300 suitable for use in an alternative embodiment of amagazine-based data cartridge library relative to library 202. Each ofthe features in FIG. 40E that is substantially identical to a feature inFIG. 40A has been give the same reference number as the feature in FIG.40A. When the magazine 1300 is operationally disposed on a shelf 1282 ofthe library 200, the magazine 1300 holds a cartridge 1284 such that: (a)a face 1286 of the cartridge 1284 with the greatest surface area lies ina vertical plane; (b) the surface vector 1288 of the face 1286 issubstantially perpendicular to or substantially parallel to a directionthat the magazine 1300 is displaced by a magazine picker 880; and (c)the cartridge 1284 is displaced in a direction 1292 in the verticalplane in which the face 1286 of the cartridge 1284 with the greatestsurface area lies that has both vertical and horizontal components, by acartridge picker 214 to insert/extract the cartridge 1284 into/from themagazine 1300.

FIG. 40F illustrates a cross-section of alternative embodiment of amagazine 1302 suitable for use in an alternative embodiment of amagazine-based data cartridge library relative to library 202. Each ofthe features in FIG. 40F that is substantially identical to a feature inFIG. 40A has been give the same reference number as the feature in FIG.40A. When the magazine 1302 is operationally disposed on a shelf 1282 ofthe library 202, the magazine 1302 holds a cartridge 1284 such that: (a)a face 1286 of the cartridge 1284 with the greatest surface area lies ina vertical plane; (b) the surface vector 1288 of the face 1286 issubstantially perpendicular or substantially parallel to a directionthat the magazine 1302 is displaced by a magazine picker 880; and (c)the cartridge 1284 is displaced in a direction 1292, a direction in thevertical plane in which the face 1286 of the cartridge 1284 with thegreatest surface area lies that has both vertical and horizontalcomponents, by a cartridge picker 214 to insert/extract the cartridge1284 into/from the magazine 1302.

With reference to FIGS. 41A-41B, an alternative embodiment of a magazine1306 is suitable for use with an alternative embodiment of amagazine-based data cartridge library relative to library 202. Each ofthe features in FIGS. 41A-41B that is substantially identical to afeature in FIG. 40A has been give the same reference number as thefeature in FIG. 40A. When the magazine 1304 is operationally disposed ona shelf 1282 of the library 202, the magazine 1304 holds a cartridge1284 such that: (a) a face 1286 of the cartridge 1284 with the greatestsurface area lies in a vertical plane; (b) the surface vector 1288 ofthe face 1286 is neither perpendicular or parallel to a direction thatthe magazine 1304 is displaced by a magazine picker 880; and (c) thecartridge 1284 is displaced in a direction 1292, a horizontal directionin the vertical plane in which the face 1286 of the cartridge 1284 withthe greatest surface area lies, by a cartridge picker 214 toinsert/extract the cartridge 1284 into/from the magazine 1304.

Also feasible is a magazine that holds cartridge 1284 in a verticalplane and in an orientation that is a combination of the orientationsthat magazine 1300 or magazine 1302 and magazine 1304 hold a cartridge1284.

As one skilled in the art will appreciate, the foregoing magazinedesigns are only exemplary of magazine designs that operatively holdmagazines in a magazine-based data cartridge library 202 in anorientation such that the face, such as the face 1286, of the cartridge,such as cartridge 1284, with the greatest surface area lies in avertical plane.

It will also be appreciated by one skilled in the art that the library202 is also operable with magazines that hold cartridges, for examplecartridge 1284, such that the face, such as the face 1286, of acartridge with the greatest surface area does not lie in a verticalplane. With reference to FIG. 42, the library 202 is operable with amagazine 1306, shown in cross-section, that when supported on a shelf1282 in the library 202, the cartridge 1284 resides in a plane that isbetween a vertical plane and a horizontal plane, shown by the arrow1285. Further, the cartridge transport 214 displaces the cartridge 1284in this plane during insertion/extraction into/from the magazine 1306.As side loading/unloading embodiment of the magazine 1306 is alsofeasible but would not be operable with the library 202 withoutmodification. These magazine 1306 designs are only exemplary of magazine1306 designs suited for use magazine-based data cartridge library 202.

With reference to FIGS. 43A-43B, the expansion of the magazine-baseddata cartridge library 202 to include an add-on unit 1310 is discussed.Generally, the library 202 is capable of being expanded to include drive180 and/or magazine 270 storage capability beyond that available in thelibrary 202. The process of expanding the library 202 comprisesobtaining the add-on unit 1310. The add-on unit 1310 can have any of anumber of combinations of elements. For example, the add-on unit 1310may be comprised entirely of shelving for storing magazines 270,entirely of drives 180 or drive bay assemblies 540 for accommodatingdrives 180, and various combinations of shelving and drives 180 or drivebay assemblies 540. The add-on unit 1310 can also comprise an entry/exitport, such as the entry/exit port 206 of the library 202. The add-onunit 1310 can also be another magazine-based data cartridge library thatis capable of functioning independently of the library 202.

With reference to FIG. 43B, the process of making the expanded library1322 is described from a schematic perspective. The library 202 has amagazine transporter space 1312 and a side 340 that is capable of beingremoved or modified so as to provide a path for transporting magazines270 between the library 202 and the add-on unit 1310. Located within themagazine transporter space 1312 are horizontally extending componentsthat are associated with the magazine transporter 212 and arecumulatively represented as horizontal components 1314. One horizontallyextending component is the guide shaft 780. Other embodiments may employa different type of rail or use a rack in a rack-and-pinion type ofdevice for moving a magazine picker 880. The add-on unit 1310 has amagazine transporter space 1316 and may or may not have horizontallyextending components. If the add-on unit 1310 has such components theyare cumulatively represented by horizontal components 1318. Generally,the add-on unit 1310 also has a side 1320 that is either removable orcapable of being altered to expose the magazine transport space 1312.Alternatively, the add-on unit 1310 may be built or designed so that themagazine space is exposed and no removal or alteration of a side isnecessary.

The process of expanding the library 202 further comprises: (a) removingor modifying the side 340 of the library 202 to expose the magazinetransporter space 1312 of the library 202; (b) removing or altering, ifnecessary, the side 1320 of the add-on unit 1300 to expose the magazinetransporter space 1316; (c) aligning the magazine transporter space 1312of the library 202 with the magazine transporter space 1316 of theadd-on 1310; and (d) replacing the horizontal components 1314 of theelevator of the library 202 that limit the horizontal movement of themagazine transport 212 and any horizontal components 1318 associatedwith the add-on 1310 that limit the horizontal movement of a magazine270 transported within the add-on 1310 with components that allow themagazine transport 212 to move within the magazine transporter space1312 of the library 202, as well as the magazine transporter space 1316of the add-on 1310. With respect to the replacing step, the guide shaft780 is replaced with a single, continuous guide shaft that allows themagazine transport 212 to function in the magazine transporter space1312 of the library 202 and the magazine transporter space 1306 of theadd-on 1310, and thereby form an expanded library 1322.

With reference to FIG. 44A, an alternative approach to replacing a guideshaft, such as the guide shaft 780, or other member that is used tohorizontally displace a magazine picker 880 is to effectively lengthenthe rod or other member by adding one or more segments to the guideshaft 780 or member. As shown in FIG. 44A, a magazine-based library1326A comprises a magazine transport space 1328A, a first magazinetransport add-on space 1330A that is typically not used when the library1326A is configured as a stand-alone device, a first side 1332A that iseither removable or modifiable to provide a path for a magazinetransport 212 to move between the first library 1326A and an add-on unit1326B, and first horizontal magazine transport components 1334A that areadapted to mate with comparable components 1334B associated with theadd-on unit 1326B. An add-on unit 1326B comprises a magazine transportspace 1328B, a second magazine transport add-on space 1330B, a secondside 1332B that is either removable or modifiable to provide a path fora magazine transport 212, and second horizontal magazine transportcomponents 1334B that are adapted to mate with the first horizontalmagazine components 1334A. In this embodiment, the first and secondsides 1332A, 1332B are either removed or appropriately modified, thefirst and second magazine transport spaces 1328A, 1328B are aligned, andthe first and second horizontal magazine transport components 1334A,1334B are mated, thereby forming an expanded library 1336.

With reference to FIG. 44B, another approach to replacing a guide shaft,such as the guide shaft 780, or other member that is used tohorizontally displace a magazine picker 880 is to effectively lengthenthe rod or other member by adding one or more segments to the guideshaft 780 or member. As shown in FIG. 44B, a magazine-based library1340A comprises a magazine transport space 1342A, a first side 1344Athat is either removable or modifiable to provide a path for a magazinetransport 212 to move between the library 1340A and an add-on unit1340B, and first horizontal magazine transport components 1346A that areadapted to mate with bridge components that, in turn, are adapted tomate with comparable components associated with the add-on unit 1340B.An add-on unit 1340B comprises a magazine transport space 1342B, asecond side 1344B that is either removable or modifiable to provide apath for a magazine transport 212, and second horizontal magazinetransport components 1346B that are adapted to mate with the bridgecomponents. In this embodiment, the first and second sides 1344A, 1344Bare either removed or appropriately modified, the first and secondmagazine transport spaces 1342A, 1342B are aligned, and the first andsecond horizontal magazine transport components 1346A, 1346B are matedto one another by an intermediate bridge component 1348, thereby formingthe expanded library 1350.

It will be appreciated by one skilled in the art that with respect tothe various methods for expanding a magazine-based data cartridgelibrary exemplified in FIGS. 43B, 44A and 44B further expansion of amagazine-based data cartridge library with additional add-on units isfeasible.

FIGS. 45A-45E illustrate various embodiments of magazine pass-thoughports that are each capable of passing a magazine 270 between a firstmagazine-based library 1354A with a first magazine transporter 1356A anda second magazine-based library 1354B with a second magazine transporter1356B. With reference to FIG. 45A, a magazine pass-through port 1358 isprovided that allows the first magazine transporter 1356A to move amagazine 270 to and from a magazine storage space 1360 that isassociated with the second magazine-based library 1354B and accessibleby the second magazine transport 1356B.

With reference to FIG. 45B, a magazine pass-through port 1362 isprovided in which first and second magazine transporters 1356A, 1356Bare each able to access a space 1364 that is located between the firstand second libraries 1354A, 1354B and pass a magazine 270 from one 1354Ato the other 1354B using the space 1364.

With reference to FIG. 45C, a magazine pass-through port 1366 isprovided that utilizes an intermediate transport device 1368 to move amagazine 270 between a first space 1370A that is accessible to a firstmagazine transporter 1356A and a second space 1370B that is accessibleto a second magazine transporter 1356B. Another embodiment uses a chuteto pass a magazine 270 from a first space associated with one library,such as the first space 1370A associated with library 1354A, to a secondspace associated with another library, such as the second space 1370Bassociated with library 1354B.

With reference to FIG. 45D, the first and second magazine-basedlibraries 1354A, 1354B are each magazine-based libraries with circularor cylindrical layouts. A magazine pass-through port 1372 is providedthat utilizes an intermediate transport device 1374 to move a magazine270 between a first space 1376A that is accessible to a first magazinetransporter 1356A and a second space 1376B that is accessible to thesecond magazine transporter 1356B. Alternatively, a magazine chute thatextends from the library 1354A to library 1354B can be used. In anotherembodiment, a second magazine chute from library 1354B to library 1354Ais also feasible.

With reference to FIG. 45E, the first and second magazine-basedlibraries 1354A, 1354B are each magazine-based libraries with circularor cylindrical layouts. A magazine pass-through port 1378 is providedthat utilizes an intermediate transport device in the form of a carouseldevice 1380 that is comprised of: (a) a carousel body 1382; and (b) apair of magazine bays 1384A, 1384B that are capable of accommodating amagazine 270 and are each accessible to the first magazine transporter1356A and the second magazine transporter 1356B depending upon therotational position of the carousel 1380. In an alternative embodiment,a carousel with one or more than two bays is feasible. The carouseldevice 1380 also comprises an electric motor (not shown) that is used torotate the carousel body 1382 about an axis 1386 as needed.

FIGS. 46A-46C are exterior, perspective views of an embodiment of amagazine data storage element 1400 that comprises a plurality of harddisk drives for storing data, a magazine for holding the drives, and aninterconnect structure for providing power to the drives andtransferring data to and/or from the drives via an interface associatedwith a magazine data storage element drive. Further, the magazine datastorage element 1400 is capable of: (a) being inserted into or exportedfrom the library 202 by the entry/exit port 206; (b) moved within thelibrary by the magazine transport 212; and (c) being supported in any ofthe locations of the shelf system 208 that are capable of supporting theLTO/SAIT magazine 270 or the DLT magazine 320, including those locationsassociated with any of the magazine bay assembly 714 that might beincorporated into the library 202. The abilities are realized by themagazine data storage element 1400 having exterior characteristics thatare substantially identical to the LTO/SAIT magazine 270 and the DLTmagazine 320. Specifically, the magazine data storage element 1400 haslength and width dimensions, orientation features, and magazineengagement features that are substantially identical to those of theLTO/SAIT magazine 270 and the DLT magazine 320. It should be appreciatedthat other embodiments of magazine data storage elements that havedifferent dimensions, different or no orientation features, anddifferent or no engagement features are feasible.

With continuing reference to FIGS. 46A-46C and FIG. 47, the magazinedata storage element 1400 comprises: (a) a plurality of hard disk drives1402, wherein a hard disk drive, herein exemplified by the serial ATAhard drive 1410, comprises of a disk recording medium (a magnetic,optical, magneto-optical or other medium), a motor for rotating the diskrecording medium, a head for reading and/or writing data from and/or tothe recording medium, an actuator for moving the head to a desiredlocation over the recording medium to facilitate a data transferoperation; (b) a magazine 1400 for holding the plurality of hard diskdrives 1402; and (c) an interconnect structure 1406 that is used toprovide power to the drives 1402 and facilitate communications withanother computer device via a magazine data storage element drive 1530of FIG. 52A.

The plurality of hard disk drives 1402 is comprised of nine hard diskdrives 1410. It should be appreciated that magazine data storageelements, such as the magazine 1400, with two or more hard disk drives1410 are feasible. Further, each of the plurality of hard disk drives1402 is a hard disk drive 1410 that employs a serial signal interface.Generally, serial signal interface hard disk drives 1410 (e.g., serialATA, serial SCSI and FibreChannel hard disk drives) have signal andpower plug interfaces that have a lower pin count than other interfaces,such as parallel SCSI. For example, the total number of pins for thesignal and power plug interfaces of a serial ATA hard disk drive istwenty-two pins. In contrast, the total number of pins for the signaland power plug interfaces of a parallel SCSI drive is seventy-two,sixty-eight signal pins and four power related pins. It should beappreciated that a magazine data storage element 1400 that uses harddisk drives with parallel signal interfaces is feasible. However, thegreater pin count associated with these drives may limit theapplicability of magazine data storage elements 1400 that employs thesetypes of drives. In the magazine data storage element 1400, each of thehard disk drives 1410 is a serial ATA, 2½″ hard disk drive 1410 thatcomprises a magnetic disk recording medium.

With reference to FIGS. 48A-48B, a serial ATA 2½″ hard disk drive 1410is generally described. The drive 1410 comprises a housing 1412 thatencloses a 2½″ diameter magnetic disk recording medium (not shown), anelectric motor (not shown) for rotating the disk recording medium, ahead structure (not shown) for reading data from and writing data to thedisk, an actuator (not shown) for moving the head structure to a desiredlocation adjacent to the disk to read data from or write data to aparticular location on the disk. The housing 1412 comprises a top face1414A, bottom face 1414B, first side face 1414C, second side face 1414D,front face 1414E, and back face 1414F. Respectively associated with thefirst side face 1414C and second side face 1414D are threaded mountingholes 1416A, 1416B and threaded mounting holes 1416C, 1416D thatfacilitate the mounting of the drive 1410 to a mounting bracket orstructure, such as cage 1432C. Associated with the back face 1414F is amale plug interface 1418 that is comprises a signal plug interface 1420and a power plug interface 1422. The signal plug interface 1420 iscomprised of seven leads, two transmit signal leads, two receive signalleads, and three ground leads. The power plug interface 1422 iscomprised of fifteen leads, nine of which are dedicated to 3.3 V, 5 Vand 12 V power signals.

With reference to FIGS. 46A-46C and FIG. 47, the magazine 1400 iscomprised of a housing 1430 and cages 1432A-1432C that each hold threeof the plurality of disk drives 1402 within the space defined by thehousing 1430. The housing 1430 is comprised of a tray 1434 and a traylid 1436 that cooperates with the tray 1434 to enclose the plurality ofdisk drives 1402. It should be appreciated that enclosing the pluralityof disk drives 1402 potentially serves a number of purposes. Forexample, enclosure provides an environment that can be controlled (e.g.,dust and temperature), facilitates stacking and storage of the magazinedata storage elements 1400 when not in use, protects the drives 1402from exterior forces etc. In certain applications, there may be littleor no benefit to be gained by enclosing the drives 1402. In such anapplication, a housing can be employed that exposes other components ofa magazine data storage element, such as element 1400.

The tray 1434 is comprised of first and second end sides 1438A, 1438B,first and second lateral sides 1440A, 1440B, and a bottom side 1442.Associated with the first end side 1438A are: (a) a first set of holes1444 that cooperate with another set of holes 1448 to allow air to bedrawn across the disk drives 1402 during operation to cool the drives1402; and (b) a first indentation 1446 for accommodating a bar codelabel or other label that identifies the magazine data storage element1400. Associated with the second end side 1438B are: (a) a second set ofholes 1448 that cooperate with the first set of holes 1444 to allow airto be drawn across the plurality of disk drives 1402 during operation tocool the drives 1402; and (b) a second indentation 1450 foraccommodating a bar code label or other label that identifies themagazine data storage element 1400. It should be appreciated that otherstructures for supporting a label, such as a sleeve, are feasible.Further, one or more RFID (Radio Frequency Identification) tags, ratherthan labels, can be associated with the magazine data storage element1400 to identify the element 1400. Also associated with the second endside 1438B is a magazine-drive connector hole 1452 that provides accessto a connector that is used to establish signal and power connectionswith a drive, such as the SATA drive 1410.

Respectively associated with the first lateral side 1440A and secondlateral side 1440B are rail 1454A and rail 1454B that function insubstantially the same manner as the rails 292A and 292B, associatedwith the LTO/SAIT magazine 270 and the DLT magazine 320. Also associatedwith the second lateral side 1440B is an insertion/ejection notch 1456that facilitates the insertion and ejection of the magazine data storageelement 1400 relative to a magazine data storage element drive 1530.

Associated with the bottom side 1442 are: (a) detents 1458A, 1458B; (b)a first pair of engagement holes 1460A, 1460B; (c) first engagement flag1462 structure that is comprised of a first pair of holes 1464A, 1464Bthat are separated from one another by a bar 1466; (d) a second pair ofengagement holes 1468A, 1468B; (e) a second engagement flag structure1470; (f) a third pair of engagement holes 1472A, 1472B; (g) a thirdengagement flag structure 1474; (h) a fourth pair of engagement holes176A, 1476B; and (i) a fourth engagement flag structure 1478. Theforegoing structures associated with the bottom side 1442 serve the samepurpose as the corresponding structures associated with the LTO/SAITmagazine 270 and the DLT magazine 320. Consequently, these structureswill not be described further. Also associated with the bottom side 1442are holes 1480A-1480F for receiving screws that are used in mounting thecages 1432A-1432C on the interior of the bottom side 1442 of the housing1430. With reference to FIG. 49, connector block mounts 1482A, 1482B areused to hold the interconnect structure 1406 in place to position themagazine-drive connector 1514 of FIG. 51A adjacent to the magazine-driveconnector hole 1452. Associated with the tray lid 1436 are holes1484A-1484D that receive screws that are used to fix the tray lid 1436in place.

With reference to FIG. 50, the cage 1432A is described with theunderstanding that cages 1432B and 1432C are substantially identical tothe cage 1432A. Cage 1432A is comprised of a top surface 1486, a pair ofmounting brackets 1488A, 1488B, and a pair of side surfaces 1490A,1490B. Associated with the top surface 1486 are a first and secondthreaded tabs 1492A, 1492B that, in the case of cages 1432B and 1432C,receive screws that pass through the holes 1484A-1484D of the tray lid1436 to fix the tray lid 1436 to the cages 1432B and 1432C. Since thecage 1432A is ultimately attached to the tray 1434, attaching the traylid 1436 to the cages 1436B, 1436C ultimately attaches the tray lid 1436to the tray 1434. Associated with the mounting brackets 1488A, 1488B arethreaded holes 1494A-1494D that receive screws that fix the cage 1432Ato the interconnect structure 1406, which is in turn connected to thebottom side 1442 of the tray 1434. Associated with the first sidesurface 1490A are a first pair of holes 1496A, 1496B, second pair ofholes 1498A, 1498B, and third pair of holes 1500A, 1500B. Similarly, afirst pair of holes 1496C, 1496D, second pair of holes 1498C, 1498D, andthird pair of holes 1500C, 1500D are associated with the second sidesurface 1490B. The groups of holes 1496A-1496D, 1498A-1498D and1500A-1500D are each used to receive screws that respectively engage thethreaded mounting holes 1416A-1416D of one of the plurality of serialATA disk drives 1410. It should be appreciated that the cage 1432A canbe adapted to accommodate a magazine data storage element 1400 thatemploys a disk drive that has a different mounting interface from thatof the serial ATA drive 1410 shown in FIGS. 48A-48B. The groups of holes1496A496D, 1498A-1498D and 1500A-1500D are spaced from one another sothat when the cage 1432A is fully populated with serial ATA drives 1410there are spaces above and below each drive through which air can passto cool the drives. To facilitate the flow of air through the spacesabove and below each of the drives, cut-outs 1502A-1502C are associatedwith the first side surface 1490A and cut-outs 1504A-1504C areassociated with the second side surface 1490B. It should be appreciatedthat different cage structures are feasible. Among these different cagestructures are cage structures that: (a) hold a different number ofdrives; (b) hold a drive in a different orientation from thatillustrated; or (c) are entirely or partially formed from the same pieceof material as the housing 1430. Also feasible are magazines that employa greater or lesser number of cage structures relative to theillustrated magazine 1400.

With reference to FIGS. 51A-51B in conjunction with FIG. 54A, theinterconnect structure 1406 is comprised of: (a) a board 1510; (b) harddisk drive connectors 1512A-1512I, each of which is capable of engagingthe plug interface 1418 of a serial ATA disk drive 1410; (c) amagazine-drive connector 1514 for engaging a drive-magazine connector1552 of a magazine data storage element drive 1530; and (d) a flexcircuit 1516 that is attached to the board 1510 and comprises electricaland/or optical conductor traces (not shown) that establish electricaland/or optical connections between the hard disk drive connectors1512A-1512L and the magazine-drive connector 1514. The magazine-driveconnector 1514 is comprised of a plurality of electrical/opticalconductive pads 1517 that are each positioned to engage the end of apin, such as a pin 1553, associated with a drive-magazine connector 1552in a magazine data storage element drive 1530. By employing a pluralityof pads 1517 instead of female connectors, pin breakage is reduced andthe degree of alignment needed to establish connections between the pads1517 and pins 1553 is reduced relative to, for example, a male/femaleconnection arrangement. It should be appreciated that an interconnectstructure that accommodates a hard disk drive with a different interfaceis feasible. Similarly, an interconnect structure with a magazine-driveconnector that accommodates a magazine data storage element drive with adifferent type of connection interface is feasible. Further, themagazine-drive connector could comprise a plurality of pins thatinterface with a drive-magazine connector that is comprised of aplurality of pads.

Also associated with the interconnect structure 1406 is electroniccircuitry 1518 that interfaces with the traces on the flex circuit 1516(electrical or optical) to perform channel multiplexing functions if themagazine-drive connector 1514 is unable to provide enough signal andpower paths for all of the drives 1402. With reference to FIG. 51C, anembodiment of the electronic circuitry 1518 that is useful in performingchannel multiplexing is described. The electronic circuitry 1518comprises a serial multiplexer 1590 that: (a) receives power and datasignals from the magazine-drive connector 1514 over a serial bus 1592;(b) multiplexes the power and data signals received from themagazine-drive connector 1514 over subsidiary buses 1594A-1594C, whichare respectively connected to drives 1596A-1596C; (c) demultiplexes datasignals received from drives 1596A-1596C over the subsidiary buses1594A-1594C; and (d) provides the demultiplexed data signals to themagazine-drive connector 1514 via the serial bus 1592. The subsidiarybuses 1594A-1594C are connected to the drives 1596A-1596C via connectors1512A-1512C. If the serial bus 1592 is a serial ATA bus, the serial bus1592 and the subsidiary serial buses 1594A-1594C are each implemented asat least twenty-two conductors on the flex circuit 1516.

With reference to FIG. 51D, if one or more of the hard disk drives 1402in the element 1400 is a parallel interface drive and there is a desireor need to have a low number of pads, such as pads 1517, associated withthe magazine-drive connector 1514, an embodiment of the electroniccircuitry 1518 can comprise a serial/parallel converter 1598 to reducethe number of pads associated with the magazine-drive connector 1514.The serial/parallel converter 1598: (a) receives power and data signalsfrom the magazine-drive connector 1514 over a serial bus 1600; (b)converts the serial power and data signals received from themagazine-drive connector 1514 to a parallel format and provides theparallel power and data signals to a parallel drive 1602 via a parallelbus 1604; (c) receives parallel data signals from the parallel drive1604; and (d) converts the parallel data signals received from theparallel drive 1604 to a serial format and provides the serial signalsto the magazine-drive connector 1514.

It should be appreciated that a magazine data storage element comprisedof serial and parallel drives is feasible. Further, a magazine datastorage element is feasible in which a multiple serial/parallelconverters are established between a serial multiplexer and multiple,parallel hard disk drives.

In addition, the electronic circuitry 1518 comprises a solid statememory, such as a EEPROM, that allows statistical data to be kept on themagazine data storage element 1400, such as the number ofmounts/dismounts to/from a drive 1410, etc. The solid state memory isalso capable of being used to define the recording media of theplurality of disk drives 1402. For example, the hard disk drives 1402could be configured as a write-once-read-many (WORM) media, as “just abunch of disks” (JBOD), or as a redundant array of independent drives(RAID).

With reference to FIG. 47, the interconnect structure 1406 alsocomprises a magazine connector block 1520 that is positioned by theconnector block mount 1482A, 1482B and cooperates with the cage 1432C tohold the magazine-drive connector 1514 in the magazine-drive connectorhole 1452 of the tray 1434.

With continuing reference to FIG. 47, the magazine data storage element1400 is further comprised of a filter 1524 that is positioned betweenthe first end side 1438A of the tray 1434 and the cage 1432A so as tocatch particulates that enter the housing 1430 via the first set ofholes 1444 while allowing air to pass between the first set of holes1444 and the second set of holes 1448 to cool the drives 1402 duringoperation.

FIGS. 52A-52B are exterior perspective views of an embodiment of amagazine data storage element drive 1530 that is capable of transferringdata to and from the magazine data storage element 1400. The drive 1530is dimensionally substantially identical to a full height LTO, SAIT orDLT drive 180 that can be used in the library 202. Consequently, thedrive 1530 is capable of being mounted in the drive bay assembly 540.Further, the plug interface in the sled portion of the drive bay 540that interfaces with the plug of the drive 1530 is substantiallyidentical to that shown in FIGS. 26A-26C. Further, the plug interface inthe housing of a drive bay 540 that accommodates a sled with a drive1530 is substantially identical to that shown in FIGS. 24A-24F. Othertypes and forms of plug interfaces are feasible.

The drive 1530 comprises a housing 1532 that is, in turn, comprised of atop wall 1534A, bottom wall 1534B, first and second side walls 1534C,1434D, front wall 1434E, and back wall 1534F. Associated with the frontwall 1534E is an opening 1536 for receiving a magazine data storageelement 1400; a grill 1538 that allows air to be moved through the drive1530 during operation to cool components of the drive 1530; and a statuspanel 1540 for providing an operator with drive 1530 status information.Associated with the back wall 1534F is a second grill 1537 thatfacilitates the flow of air through the drive 1530 during operation. Aplug interface 1544 for receiving data related signals and power is alsoassociated with the back wall 1434F. The plug interface 1544 issubstantially identical to the plug interface on a comparable SAITdrive. Other plug interfaces are feasible.

With reference to FIGS. 53A-53D, the drive 1530 is further comprised ofa chassis 1550 that generally provides a mounting surface for otherelements that comprise the drive 1530. In this regard, the chassis 1550provides a mounting surface to which the bottom wall 1534B, first andsecond side walls 1534C, 1534D, front wall 1534E, and back wall 1534Fare directly mounted. The chassis 1550 also provides a mounting surfacefor: (a) a drive-magazine connector 1552 that interfaces with themagazine-drive connector 1514 of the magazine data storage element 1400;(b) a magazine guide structure 1554 that cooperates with the rails1454A, 1454B of the magazine data storage element 1400 to align themagazine-drive connector 1514 of the magazine data storage element 1400with the drive-magazine connector 1552; and (c) a magazineinsertion/ejection system 1556 that is used to force the magazine-driveconnector 1514 of the magazine data storage element 1400 into engagementwith the drive-magazine connector 1552 during an insertion operation andout of engagement with the drive-magazine connector 1552, for example,during an ejection operation. Also attached to the chassis 1550 is acontroller board 1584 that comprises electronic circuitry forcontrolling the operation of the drive 1530 relative to a magazine datastorage element 1400. In this regard the controller board 1584 providesthe ability to manage or configure the hard disk drives 1402 associateda magazine data storage element 1400. In one embodiment, the controllerboard 1584 is capable of configuring the hard disk drives 1402 as aredundant array of independent drives (RAID) or as just a bunch ofdrives (JBOD). A fan 1586 is attached to the back wall 1534F and isused, during operation, to pull air across the controller board 1584 andthrough a magazine data storage element, such as element 1400, to coolthe board and the hard disk drives 1402 within the element 1400.

The drive-magazine connector 1552 is comprised of a plurality ofspring-loaded pins 1553. The free end of each of the pins 1553 ispositioned to engage a corresponding conductive pad 1517 associated withthe magazine-drive connector 1514 when the magazine data storage element1400 is properly inserted into the drive 1530. Most, if not all, of thepins 1553 are connected to the plug interface 1544 by conductors 1553.If the magazine-drive connector 1514 comprises optical pads/receivers,the drive-magazine connector 1552 employs an optical “pin” structurethat is capable of engaging the optical receiver. It should beappreciated that the magazine-drive connector 1514 may comprise one ormore optical pads/receivers and one or more electrically conductivepads. In which case, the drive-magazine connector 1552 and theconductors 1553 are adapted accordingly. Spring loaded pins 1553 areemployed to reduce the occurrence of broken pins that could disable thedrive 1530. Further, the use of spring loaded pins 1553 and pads 1517 toestablish a connection between a magazine data storage element 1400 andthe drive 1530 allows some alignment tolerance relative to amale/females connection structure, i.e., the magazine-drive connector1514 of a magazine data storage element 1400 does not need to be asaccurately aligned to engage the drive-magazine connector 1552 as wouldbe the case if the magazine-drive connector 1514 employed a plurality offemale sockets. It should be appreciated that a drive-magazine connectorcould comprise a plurality of pads 1517 that interface with amagazine-drive connector that is comprised of a plurality of pins 1553.Other types of connection interfaces are feasible. For instance, amale/female connection interface is feasible. However, as previouslynoted, such an interface is likely to have more pin breakages andtighter alignment tolerances.

The magazine guide structure 1554 is comprised of first and second guiderails 1558A, 1558B that cooperate with the rails 1454A, 1454B of themagazine data storage element 1400 to assure that the magazine datastorage element 1400 is oriented so that the magazine-drive connector1514 appropriately interfaces with the drive-magazine connector 1552.

The magazine insertion/ejection system 1556 is comprised of: (a) a camplate 1560; (b) a cam ramp 1562; (c) a cam hook 1564; (d) a lead screwnut 1566; (e) a pin 1568 that pivotally attaches the cam hook 1564 tothe lead screw nut 1566; (f) a lead screw 1570 that receives the leadscrew nut 1566; (g) a lead screw mounting block 1572 that provides abearing mount for one end of the lead screw 1570; (h) a lead screw andmotor mounting block 1574 that provides a bearing mount for the otherend of the lead screw 1570 and a mount for a DC motor 1576; (i) the DCmotor 1576 for providing the rotational motive force that is used tomove the lead screw nut 1566 back and forth along the lead screw 1570;(j) a pinion 1578 that is operatively attached to the drive shaft (notshown) of the DC motor 1576; and (k) a gear 1580 that is attached to thelead screw 1570 and cooperates with the pinion 1578 to transmit therotational motive force produced by the DC motor 1576 to the lead screw1570.

In operation, the magazine insertion/ejection system 1556 is either in adisengaged state or an engaged state. FIG. 54A illustrates thedisengaged state of the system 1556. In the disengaged state, the camhook 1564 is positioned so as not to be able to engage the notch 1456associated with the housing 1430 of the magazine data storage element1400. This positioning of the cam hook 1564 is achieved by using the DCmotor 1576 to drive the lead screw nut 1566 and the cam hook 1564towards the lead screw mounting block 1572. As the lead screw nut 1566and cam hook 1564 approach the lead screw mounting block 1572, a surface1582 of the cam hook 1564 engages the cam ramp 1562. As the lead screwnut 1566 is driven further towards the lead screw mounting block 1572,the cam ramp 1562 applies a force to the cam hook 1564 via the surface1582 that causes the cam hook 1564 to rotate to a position at which thecam hook 1564 is not able to engage the notch 1456.

FIG. 54B illustrates the engaged state of the system 1556. In theengaged state, the cam hook 1564 is positioned to engage the notch 1456associated with the housing 1430 of the magazine data storage element1400. This positioning of the cam hook 1564 is achieved by using the DCmotor 1576 to drive the lead screw nut 1566 and the cam hook 1564 to aposition at which the surface 1582 of the cam hook 1564 is immediatelyadjacent to, but not engaging the cam ramp 1562. Once the cam hook 1564has engaged the notch 1456, movement of the cam hook 1564 between thestart of the cam ramp 1562 and the lead screw/motor mounting block 1574is used to apply either a force that drives the element 1400 towards thedrive-magazine connector 1552 or a force that drives the element 1400away from the drive-magazine connector 1552.

The manner in which the magazine data storage element 1400 is movedwithin the library 202 is substantially identical to the manner in whicha data cartridge magazine 466 is moved within the library 202.Specifically, the manner in which the magazine data storage element 1400is moved into and out of the library 202 via the entry/exit port 206 issubstantially identical to the manner in which the data cartridgemagazine 466 is moved into and out of the library 202 via the entry/exitport 206 and described with respect to FIGS. 19A-19E. Likewise, themanner in which the magazine data storage element 1400 is moved awayfrom a shelf, such as shelf 990, and towards a shelf 990 issubstantially identical to the manner in which the magazine 988 is movedtowards and away from a shelf 990 and described with respect to FIGS.31A-31L. With reference to FIGS. 55A-55D, the manner in which themagazine data storage element 1400 is loaded into the drive 1530 is, inpart, substantially identical the magazine 988 is moved towards a shelf,such as shelf 992, and described with respect to FIGS. 31H-31L. However,once the magazine data storage element 1400 is in the positionillustrated in FIG. 55D, the drive 1530 employs the magazineinsertion/ejection system 1556 to force the magazine data storageelement 1400 towards the drive-magazine connector 1552 so that themagazine-drive connector 1514 engages the drive-magazine connector 1552.An optical detector 1608 is used to determine when the magazine datastorage element 1400 is in the appropriate position for theinsertion/ejection system 1556 to be employed. The insertion/ejectionsystem 1556 is not activated, however, until the magazine picker 880 isdisengaged from the magazine data storage element 1400. Once themagazine data storage element 1400 is disengaged from the magazinepicker 880, the insertion/ejection system 1556 is transitioned from thedisengaged state to the engaged state and used to force the element 1400towards the drive-magazine connector 1552. The insertion/ejection system1556 ceases forcing the element 1400 toward the drive-magazine connector1552 once a connection has been established between the magazine-driveconnector 1514 and the drive-magazine connection 1552. Confirmation thata connection has been established is determined using two of the pads,such as pads 1517, of the magazine-drive connector 1514 that areconnected together. To elaborate, a connection is confirmed when asignal from the drive-magazine connector 1552 is applied to one of thetwo pads and returned to the magazine-drive connector 1514 from theother pad. Other structures for determining when to cease forcing theelement 1400 towards the drive magazine connector 1552 are feasible. Forinstance, a second optical detector (not shown) can be employed or anencoder associated with the motor 1576.

Unloading of the magazine data storage element 1400 from the drive 1530involves using the magazine insertion/ejection system 1556 to force themagazine data storage element away from the drive-magazine connector1552 so that the magazine-drive connector 1514 disengages from thedrive-magazine connector 1552. Unloading is completed by reversing thesequence of operations illustrated in FIGS. 55A-55D.

At this point, it should be appreciated a magazine-based library 202comprised of one or more magazine data storage element drives, such asdrive 1530, one or more other drives, such as a tape drive 180, that areeach capable of operating on a data cartridge, such as an LTO cartridge1244, a shelving system 208 that is capable of storing at least onemagazine data storage element 1400 and at least one data cartridgemagazine, such as magazine 320, a magazine transport 108, and acartridge transport 110 is feasible. For example, a library comprised ofone or more drives 1530, one more LTO, SAIT or DLT tape cartridge drives180, the shelving system 208 that is capable of storing the magazinedata storage element 1400 and one of the data cartridge magazines 270,320, the magazine transport 212, and a cartridge transport 214 isfeasible. Also feasible is a magazine-based library that operates solelyon magazine data storage elements 1400. For example, a library comprisedof one or more of the drives 1530, the shelving system 208 that iscapable of storing one or more of the magazine data storage element1400, and the magazine transport 214 is feasible. If the library 202 isused for such a magazine-based library, the elements of the library 202associated with moving cartridges in the library can be eliminated. Itshould also be appreciated that the magazine data storage element 1400is also capable of being transported between magazine-based libraries orsections of magazine-based libraries in the same manner that datacartridge magazines, such as magazine 320, can be transported betweenmagazine-based data cartridge libraries or sections thereof. Alsofeasible is a non-library implementation in which a magazine datastorage element drive is capable of being directly connected to a hostcomputer. For example, the drive 1530 can be directly connected to ahost computer, such as a PC (Personal Computer). In such animplementation, a magazine data storage element 1400 would beloaded/unloaded into/from a magazine data storage element drive, such asdrive 1530, by hand.

1. A data storage library comprising: an interior environment and anexterior environment substantially defined by a library frame; anopening in the frame providing access to a mounting structure, themounting structure adapted to accommodate either a shelf module, thataccommodates disposition of a magazine storage element, or a drivemodule, that is capable of accessing data retained in memory in themagazine storage element, wherein when the mounting structureaccommodates the drive module both the opening is substantiallyobstructed and the drive module maintains accessibility from theexterior environment; a power source and communication pathwayassociated with the mounting structure adapted to provide power andcommunication to the drive module; a magazine transport that issubstantially confined to operate within the interior environment, themagazine transport capable of moving the magazine storage element toeither the drive module or shelf module accommodated by the mountingstructure.
 2. The data storage library of claim 1 wherein the magazinestorage element is selected from the group consisting of: a magneticdisk drive magazine comprising a plurality of magnetic disk drives, asolid state memory magazine comprising a plurality of non-movingrecording media, a magneto-optical magazine comprising a plurality ofmagneto-optical storage devices, an optical drive magazine comprising aplurality of optical recording devices, a magazine comprising aplurality of tape cartridges.
 3. The data storage library of claim 1wherein the drive module comprises at least one docking station adaptedto receive the magazine storage element via a docking station openingthat is accessible to the magazine transport.
 4. The data storagelibrary of claim 1 wherein the frame provides a second opening adaptedto receive either a drive module or a shelf module wherein when saiddrive module is disposed in said second opening, said drive modulesubstantially obstructs the second opening and yet is accessible fromthe exterior environment.
 5. The data storage library of claim 1 furthercomprises a means for attaching the shelf module and the drive module tothe frame.
 6. A magazine-based data cartridge library comprising: ashelf system where at least a first disk drive magazine and a seconddisk drive magazine can be disposed; at least a first docking stationadapted to cooperate with each of the first and second disk drivemagazines to provide power and a communication link with the library; arobotic magazine transport capable of transporting one of the first andsecond disk drive magazines from the shelf system into a position ofcooperation with the first docking station; and an operator alterablespace substantially defined by a frame of the library and adapted toaccommodate one of a plurality of interchangeable modules including ashelf module and a drive module, the shelf module adapted to accommodateat least a third disk drive magazine and the drive module adapted toaccommodate at least a second docking station, the shelf module capableof being used in substitution for the drive module through an opening inthe frame.
 7. The magazine-based data cartridge library of claim 6further comprising a second operator alterable space.
 8. Themagazine-based data cartridge library of claim 6 wherein the openingaccessible from an exterior location relative to the library.
 9. Themagazine-based data cartridge library of claim 6 wherein the operatoralterable space comprises a mounting structure adapted to fixedly mountone of the modules.
 10. The magazine-based data cartridge library ofclaim 6 wherein the robotic magazine transport is interposed in atransport space between the shelf system and the operator definablespace.
 11. The magazine-based data cartridge library of claim 6 whereinthe shelf module is adapted to receive the third data cartridge magazinethrough a magazine opening facing the transport space.
 12. Themagazine-based data cartridge library of claim 6 wherein the dockingstation module comprises a plurality of drive bays adapted to receive atleast the second docking station.
 13. The magazine-based data cartridgelibrary of claim 12 wherein the docking station bays are adapted toreceive at least the second docking station through a drive bay openingaccessible from an exterior location relative to the library.
 14. Amethod comprising: providing a magazine-based library possessing anoperator alterable space adapted to accommodate either a shelf module ora drive module wherein the shelf module is adapted to support at least afirst magazine storage element and a second magazine storage element;the drive module is adapted to access one of the first and secondmagazine storage elements for reading and writing data; and a roboticmagazine transport capable of transporting one of the first and secondmagazine storage elements from the shelf module into a position for thedrive module to access the magazine to read and write data; accessingthe operator alterable space via an accommodating opening in a frameassociated with the magazine-based library, the frame defining aninterior environment in the magazine-based library; inserting the drivemodule into the operator alterable space through the opening from alocation outside of the interior environment wherein the drive modulesubstantially obstructs the accommodating opening in the frame when thedrive module is inserted in the opening, the drive module remainingaccessible from outside the interior environment when inserted in theopening and the drive module accessible to the robotic magazine;providing power to the drive module through a power source provided bythe library.
 15. The method of claim 14 further comprising positioningthe magazine via the magazine transport to a docking station openingadapted to receive the magazine and linking the magazine to the libraryvia the docking station.
 16. The method of claim 14 further comprising:detaching the drive module from a mounting structure associated with theoperator alterable space; disengaging the power from a power source thatprovides power to the drive module; removing the drive module from thelibrary through the accommodating opening from outside the interiorenvironment.
 17. The method of claim 16 further comprising: inserting ashelf module through the accommodating opening from outside the interiorenvironment and attaching the shelf module fixedly to the mountingstructure.
 18. The method of claim 17 further comprising positioning themagazine transport to a shelf opening of the shelf module from theinterior environment and displacing the magazine from the shelf modulevia the magazine transport.
 19. The method of claim 14 wherein themagazine-based library possesses a second operator alterable space thatis essentially contiguous to the operator alterable space.